{"product_id":"fish-dox-100mg-30-tablets","title":"Fish Doxy (Doxycycline) Capsules Fish Antibiotics","description":"\u003c!-- \n  SEO Title: Fish Doxy (Doxycycline) Capsules for Aquarium Fish: Dosage, Treatment Guide \u0026 Expert Comparisons\n  Meta Description: Fish Doxy (Doxycycline) capsules provide versatile broad-spectrum treatment for bacterial infections in aquarium fish — fin rot, columnaris, septicemia, mouth rot \u0026 more. Dosage chart, step-by-step guide, comparisons \u0026 FAQs. No prescription needed.\n  Primary Keyword: Fish Doxy\n  Secondary Keywords: fish doxycycline, doxycycline fish antibiotics, Fish Doxy capsules, aquarium doxycycline, doxycycline for fish, tetracycline fish antibiotic, fish doxy dosage\n--\u003e\n\n\u003c!-- Schema: FAQPage --\u003e\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\"@type\":\"Question\",\"name\":\"What is the correct dosage of Fish Doxy for aquarium fish?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Dissolve the contents of one 100 mg capsule per 10 gallons of actual water volume. Repeat every 24 hours for 5 to 10 days, performing a 20–25% water change before each new dose.\"}},\n    {\"@type\":\"Question\",\"name\":\"Is Fish Doxy safe for freshwater and saltwater aquariums?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Yes. Unlike older tetracycline hydrochloride, doxycycline is not significantly deactivated by calcium or hard water, making it effective in both freshwater and saltwater environments.\"}},\n    {\"@type\":\"Question\",\"name\":\"What is the difference between Fish Doxy and Fish Mox?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Fish Mox contains amoxicillin (penicillin class, bactericidal). Fish Doxy contains doxycycline (tetracycline class, bacteriostatic). Fish Doxy offers broader coverage including atypical bacteria like Chlamydia, Mycoplasma, and Rickettsia, and is preferred when the diagnosis is unclear or the infection has not responded to penicillin-class antibiotics.\"}},\n    {\"@type\":\"Question\",\"name\":\"Can Fish Doxy treat columnaris?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Yes. Doxycycline is considered the most effective tetracycline-class antibiotic for columnaris. It is often recommended when standard treatments fail to control this aggressive disease.\"}},\n    {\"@type\":\"Question\",\"name\":\"Will Fish Doxy discolor my aquarium water?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Yes. Doxycycline typically causes a temporary yellow or amber discoloration of aquarium water. This is harmless and clears after treatment when activated carbon filtration is restored.\"}},\n    {\"@type\":\"Question\",\"name\":\"Do I need a prescription to buy Fish Doxy?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. Fish Doxy is sold over-the-counter for ornamental fish use in the United States. No veterinary prescription is required.\"}}\n  ]\n}\n\u003c\/script\u003e\n\n\u003c!-- Schema: Product --\u003e\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"Product\",\n  \"name\": \"Fish Doxy (Doxycycline) 100mg Capsules\",\n  \"description\": \"Broad-spectrum tetracycline antibiotic capsules for treating bacterial infections in ornamental aquarium fish. Effective against gram-positive, gram-negative, and atypical bacteria including Chlamydia and Mycoplasma.\",\n  \"category\": \"Pet Supplies \u003e Fish Supplies \u003e Fish Medications\",\n  \"brand\": {\"@type\":\"Brand\",\"name\":\"Fish Doxy\"},\n  \"activeIngredient\": \"Doxycycline Hyclate 100mg\"\n}\n\u003c\/script\u003e\n\n\u003c!-- Schema: HowTo --\u003e\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"HowTo\",\n  \"name\": \"How to Treat Aquarium Fish with Fish Doxy (Doxycycline)\",\n  \"description\": \"Step-by-step guide to treating bacterial infections in aquarium fish using Fish Doxy doxycycline capsules.\",\n  \"step\": [\n    {\"@type\":\"HowToStep\",\"name\":\"Confirm Bacterial Infection\",\"text\":\"Look for frayed fins, discoloration, open sores, mouth erosion, lethargy, or erratic swimming. Rule out parasitic and fungal causes.\"},\n    {\"@type\":\"HowToStep\",\"name\":\"Prepare a Hospital Tank\",\"text\":\"Set up a separate treatment tank. Remove activated carbon, turn off UV sterilizers, and dim lights.\"},\n    {\"@type\":\"HowToStep\",\"name\":\"Calculate the Dose\",\"text\":\"Use one 100 mg capsule per 10 gallons of actual water volume.\"},\n    {\"@type\":\"HowToStep\",\"name\":\"Dissolve and Administer\",\"text\":\"Open the capsule, dissolve the powder in a cup of tank water, then pour across the water surface. Water will turn yellow — this is normal.\"},\n    {\"@type\":\"HowToStep\",\"name\":\"Repeat Daily for 5–10 Days\",\"text\":\"Perform a 20–25% water change every 24 hours, then add a fresh dose.\"},\n    {\"@type\":\"HowToStep\",\"name\":\"Post-Treatment Recovery\",\"text\":\"Reintroduce carbon filtration to clear water discoloration. Add aquarium probiotics and monitor fish before returning to the main display.\"}\n  ]\n}\n\u003c\/script\u003e\n\n\u003ch1\u003eFish Doxy (Doxycycline) Capsules for Aquarium Fish: Complete Dosage, Treatment \u0026amp; Comparison Guide\u003c\/h1\u003e\n\n\u003cp\u003eSome bacterial infections are straightforward — a clear case of fin rot that responds quickly to a first-line antibiotic. But what happens when the diagnosis is unclear, multiple pathogens may be at play, or a stubborn infection simply refuses to respond to amoxicillin or cephalexin? That is exactly when experienced aquarists turn to Fish Doxy.\u003c\/p\u003e\n\n\u003cp\u003ePowered by doxycycline hyclate — a versatile tetracycline antibiotic with one of the broadest spectrums of activity available in the aquarium hobby — Fish Doxy covers gram-positive bacteria, gram-negative bacteria, and atypical organisms like \u003cem\u003eChlamydia\u003c\/em\u003e, \u003cem\u003eMycoplasma\u003c\/em\u003e, and \u003cem\u003eRickettsia\u003c\/em\u003e that most other aquarium antibiotics simply cannot reach. It is the antibiotic you keep in your fishkeeping toolkit for the infections that other medications struggle to resolve.\u003c\/p\u003e\n\n\u003cp\u003eThis comprehensive guide covers everything you need: what Fish Doxy is and how it works, which diseases it targets, exact dosage instructions, tank preparation, critical differences from other aquarium antibiotics, and what to expect during and after treatment.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eImportant Notice:\u003c\/strong\u003e Fish Doxy is intended exclusively for ornamental and aquarium fish. It is not for human consumption. We do not sell or recommend this product for human use. Always consult a qualified aquatic veterinarian if you are unsure about diagnosis or treatment.\u003c\/p\u003e\n\n\u003ch2\u003eWhat Is Fish Doxy?\u003c\/h2\u003e\n\n\u003cp\u003eFish Doxy is the aquarium hobby's established trade name for doxycycline hyclate capsules formulated for ornamental fish. Doxycycline is a semi-synthetic antibiotic belonging to the tetracycline class — a family of medications discovered in the 1940s and prized for their exceptionally broad spectrum of antimicrobial activity.\u003c\/p\u003e\n\n\u003cp\u003eWhat sets doxycycline apart from older tetracyclines (like tetracycline hydrochloride) is its superior pharmacological profile. Doxycycline is lipid-soluble, which gives it better tissue penetration, a longer half-life, and — critically for aquarium use — it is not significantly deactivated by calcium, magnesium, or hard water. Older tetracyclines bind to dissolved minerals in aquarium water and lose effectiveness, especially in saltwater or hard freshwater. Doxycycline avoids this problem, making it the only tetracycline-class antibiotic truly suited for diverse aquarium environments.\u003c\/p\u003e\n\n\u003cp\u003eFish Doxy capsules contain 100 mg of doxycycline hyclate per capsule and are available in 30-count and 60-count bottles. The pull-apart capsule design allows the powder to be dissolved directly in tank water or mixed into fish food for targeted internal delivery.\u003c\/p\u003e\n\n\u003ch3\u003eProduct Details at a Glance\u003c\/h3\u003e\n\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n\u003cth\u003eAttribute\u003c\/th\u003e\n\u003cth\u003eDetails\u003c\/th\u003e\n\u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eActive Ingredient\u003c\/td\u003e\n\u003ctd\u003eDoxycycline Hyclate 100 mg\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDrug Class\u003c\/td\u003e\n\u003ctd\u003eTetracycline (Semi-Synthetic, Broad-Spectrum)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eMechanism\u003c\/td\u003e\n\u003ctd\u003eBacteriostatic — inhibits bacterial protein synthesis at the 30S ribosomal subunit\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eFormulation\u003c\/td\u003e\n\u003ctd\u003ePull-apart capsule (powder dissolves in water or mixes with food)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eAvailable Counts\u003c\/td\u003e\n\u003ctd\u003e30 capsules and 60 capsules\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eSpectrum of Activity\u003c\/td\u003e\n\u003ctd\u003eGram-positive, gram-negative, and atypical organisms (Chlamydia, Mycoplasma, Rickettsia)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eCommon Brand Names\u003c\/td\u003e\n\u003ctd\u003eFish Doxy, Fix Doxy, Bird Biotic, Aqua Doxycycline\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eRegulatory Status (USA)\u003c\/td\u003e\n\u003ctd\u003eOTC — no prescription required for ornamental fish\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eKnown Side Effect\u003c\/td\u003e\n\u003ctd\u003eTemporary yellow\/amber water discoloration (harmless)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eStorage\u003c\/td\u003e\n\u003ctd\u003eCool, dry place, away from light and moisture — light sensitive\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eCommon Fish Diseases Treated by Fish Doxy\u003c\/h2\u003e\n\n\u003cp\u003eDoxycycline's exceptionally broad spectrum makes Fish Doxy the most versatile antibiotic in the aquarium medicine cabinet. It handles the standard bacterial pathogens that cause everyday aquarium diseases, but its real value lies in its ability to also target atypical and intracellular organisms that other antibiotics miss entirely.\u003c\/p\u003e\n\n\u003ch3\u003eColumnaris Disease\u003c\/h3\u003e\n\u003cp\u003eCaused by \u003cem\u003eFlavobacterium columnare\u003c\/em\u003e, columnaris is one of the most aggressive and feared aquarium diseases — producing white or grayish cotton-like patches on the skin, mouth, and fins that can kill within days. Doxycycline is widely regarded as the most effective tetracycline-class antibiotic for columnaris. Where older tetracycline hydrochloride often fails against this pathogen, Fish Doxy delivers consistent results and is frequently a first-choice treatment for this disease.\u003c\/p\u003e\n\n\u003ch3\u003eFin and Tail Rot\u003c\/h3\u003e\n\u003cp\u003eProgressive erosion of fin tissue caused by \u003cem\u003eAeromonas\u003c\/em\u003e, \u003cem\u003ePseudomonas\u003c\/em\u003e, and \u003cem\u003eFlavobacterium\u003c\/em\u003e species responds well to doxycycline's broad coverage. Fish Doxy is particularly useful for fin rot that has not responded to narrower-spectrum antibiotics, suggesting a mixed bacterial population driving the infection.\u003c\/p\u003e\n\n\u003ch3\u003eMouth Rot (Oral Bacterial Infection)\u003c\/h3\u003e\n\u003cp\u003eBacterial erosion around the mouth and jaw interferes with the fish's ability to eat and can rapidly become life-threatening. Fish Doxy's broad-spectrum activity covers the diverse range of bacteria commonly implicated in oral infections.\u003c\/p\u003e\n\n\u003ch3\u003eBacterial Gill Disease\u003c\/h3\u003e\n\u003cp\u003eLabored breathing, flared gill covers, and mucus buildup indicate gill disease. Doxycycline dissolved in water is absorbed directly through the gills, delivering the antibiotic straight to the infection site.\u003c\/p\u003e\n\n\u003ch3\u003eHemorrhagic Septicemia\u003c\/h3\u003e\n\u003cp\u003eRed streaks through fins, subcutaneous hemorrhaging, and lethargy point to septicemia — a systemic blood infection commonly caused by \u003cem\u003eAeromonas\u003c\/em\u003e or \u003cem\u003ePseudomonas\u003c\/em\u003e. Fish Doxy's gram-negative coverage and lipid-soluble tissue penetration make it a strong option for systemic infections.\u003c\/p\u003e\n\n\u003ch3\u003eSkin Ulcers and Open Sores\u003c\/h3\u003e\n\u003cp\u003eUlcerative lesions caused by \u003cem\u003eAeromonas hydrophila\u003c\/em\u003e or \u003cem\u003eVibrio\u003c\/em\u003e species respond to doxycycline treatment. The drug's lipid solubility allows deeper tissue penetration than many water-soluble antibiotics.\u003c\/p\u003e\n\n\u003ch3\u003ePop-Eye (Exophthalmia)\u003c\/h3\u003e\n\u003cp\u003eBulging eyes from bacterial infection behind the eye socket benefit from doxycycline's deep tissue penetration, especially when the specific pathogen is unknown or the infection involves mixed bacteria.\u003c\/p\u003e\n\n\u003ch3\u003eSwim Bladder Infections\u003c\/h3\u003e\n\u003cp\u003eWhen swim bladder dysfunction is bacterial in origin, Fish Doxy delivered through medicated food can help address the underlying infection in the internal organ.\u003c\/p\u003e\n\n\u003ch3\u003eInfections Involving Atypical Bacteria\u003c\/h3\u003e\n\u003cp\u003eThis is where Fish Doxy stands alone among aquarium antibiotics. Doxycycline is active against intracellular and atypical pathogens — including \u003cem\u003eChlamydia\u003c\/em\u003e, \u003cem\u003eMycoplasma\u003c\/em\u003e, and \u003cem\u003eRickettsia\u003c\/em\u003e species — that amoxicillin, cephalexin, and even ciprofloxacin cannot effectively target. When an infection persists despite multiple antibiotic courses, or when chronic wasting suggests an unusual pathogen, Fish Doxy may succeed where others have failed.\u003c\/p\u003e\n\n\u003ch2\u003eHow Does Fish Doxy Work?\u003c\/h2\u003e\n\n\u003cp\u003eDoxycycline is a bacteriostatic antibiotic. It stops bacteria from growing and reproducing by binding to the 30S ribosomal subunit inside bacterial cells, blocking the attachment of transfer RNA (tRNA) to the ribosome and halting protein synthesis. Without new proteins, bacteria cannot multiply, and the fish's own immune system clears the stalled infection.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eKey pharmacological advantages of doxycycline in aquarium use:\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReduced toxin release:\u003c\/strong\u003e Bactericidal antibiotics that kill bacteria rapidly can trigger a toxic die-off spike as endotoxins flood the water. Doxycycline's slower, growth-halting approach avoids this problem.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAnti-inflammatory properties:\u003c\/strong\u003e Tetracyclines possess immunomodulatory properties that reduce inflammation independently of antibacterial action — accelerating visible improvement in swollen, irritated fish tissue.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSuperior tissue penetration:\u003c\/strong\u003e Lipid-soluble doxycycline crosses cell membranes and reaches intracellular pathogens that water-soluble antibiotics cannot access.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCalcium resistance:\u003c\/strong\u003e Unlike tetracycline hydrochloride, doxycycline is not significantly deactivated by dissolved calcium and magnesium. It remains potent in hard freshwater and saltwater — a critical advantage for marine aquarists.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eLonger half-life:\u003c\/strong\u003e Doxycycline persists in tissue longer than standard tetracycline, maintaining therapeutic levels between daily doses.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWidest coverage in the toolkit:\u003c\/strong\u003e Gram-positive, gram-negative, and atypical organisms are all within range — making Fish Doxy the most versatile single antibiotic available to aquarists.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eFish Doxy Dosage and Administration Guide\u003c\/h2\u003e\n\n\u003cp\u003eCorrect dosing is essential. Doxycycline's bacteriostatic mechanism requires consistent therapeutic concentrations in the water to keep bacteria suppressed throughout the course.\u003c\/p\u003e\n\n\u003ch3\u003eStandard Dosage Chart\u003c\/h3\u003e\n\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n\u003cth\u003eCapsule Strength\u003c\/th\u003e\n\u003cth\u003eTank Volume\u003c\/th\u003e\n\u003cth\u003eFrequency\u003c\/th\u003e\n\u003cth\u003eDuration\u003c\/th\u003e\n\u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e100 mg\u003c\/td\u003e\n\u003ctd\u003e10 gallons\u003c\/td\u003e\n\u003ctd\u003eEvery 24 hours\u003c\/td\u003e\n\u003ctd\u003e5–10 days\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e100 mg (x2)\u003c\/td\u003e\n\u003ctd\u003e20 gallons\u003c\/td\u003e\n\u003ctd\u003eEvery 24 hours\u003c\/td\u003e\n\u003ctd\u003e5–10 days\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e100 mg (x3)\u003c\/td\u003e\n\u003ctd\u003e30 gallons\u003c\/td\u003e\n\u003ctd\u003eEvery 24 hours\u003c\/td\u003e\n\u003ctd\u003e5–10 days\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003cp\u003e\u003cstrong\u003eImportant:\u003c\/strong\u003e Always dose based on actual water volume. Substrate, decorations, and equipment typically reduce usable water by 15–20%.\u003c\/p\u003e\n\n\u003ch3\u003eHow to Administer Fish Doxy\u003c\/h3\u003e\n\n\u003col\u003e\n  \u003cli\u003e\n\u003cstrong\u003eEstimate actual water volume.\u003c\/strong\u003e Subtract approximately 15–20% from your tank's rated capacity.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eOpen the capsule.\u003c\/strong\u003e Empty the powder into a small cup of tank water. Stir until dissolved. The water will turn yellow or amber — this is normal and harmless.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAdd to the aquarium.\u003c\/strong\u003e Pour evenly across the water surface or near a filter outflow.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRepeat every 24 hours\u003c\/strong\u003e for 5 to 10 days.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePerform a 20–25% water change\u003c\/strong\u003e before each new dose.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAfter the final dose,\u003c\/strong\u003e run activated carbon filtration for 24–48 hours to clear residual medication and water discoloration.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch3\u003eAlternative: Medicated Food Delivery\u003c\/h3\u003e\n\u003cp\u003eFor internal infections (septicemia, swim bladder disease, chronic wasting), open the capsule and mix the powder into gel food, soaked pellets, or frozen bloodworms. Feed once daily for 5–10 days. This delivers doxycycline directly through the digestive tract for maximum internal absorption.\u003c\/p\u003e\n\n\u003ch3\u003eFreshwater vs. Saltwater Use\u003c\/h3\u003e\n\u003cp\u003eFish Doxy is one of the best antibiotic choices for saltwater aquariums. Doxycycline maintains its potency in marine environments where tetracycline hydrochloride becomes ineffective due to calcium binding. Always treat in a hospital tank when your marine system contains invertebrates or corals.\u003c\/p\u003e\n\n\u003ch2\u003eTank Preparation and Water Parameters\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRemove activated carbon\u003c\/strong\u003e from all filters.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTurn off UV sterilizers.\u003c\/strong\u003e Doxycycline is photosensitive — UV and strong ambient light degrade it.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDim aquarium lighting\u003c\/strong\u003e or keep lights off during the treatment course to maintain drug potency.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePerform a 20–25% water change\u003c\/strong\u003e before the first dose.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTest and stabilize water parameters:\u003c\/strong\u003e ammonia and nitrite at 0 ppm, nitrate below 20 ppm, temperature stable for your species.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eUse a hospital or quarantine tank whenever possible.\u003c\/strong\u003e This isolates the sick fish, conserves medication, protects beneficial bacteria, and keeps the yellow water discoloration out of your display tank.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eStep-by-Step Treatment Guide\u003c\/h2\u003e\n\n\u003ch3\u003eStep 1: Confirm the Infection Is Bacterial\u003c\/h3\u003e\n\u003cp\u003eLook for bacterial indicators: frayed fins, red streaks, open sores, discolored patches, mouth erosion, labored breathing, body swelling, or erratic swimming. Rule out fungal and parasitic causes. Fish Doxy treats bacteria — it has no activity against fungal pathogens.\u003c\/p\u003e\n\n\u003ch3\u003eStep 2: Consider Fish Doxy When the Diagnosis Is Unclear\u003c\/h3\u003e\n\u003cp\u003eIf you are unsure whether the pathogen is gram-positive, gram-negative, or atypical, doxycycline covers all three categories. This makes it an excellent choice for ambiguous symptoms, mixed infections, or cases that have not responded to \u003ca href=\"\/collections\/fish-mox\"\u003eFish Mox\u003c\/a\u003e or \u003ca href=\"\/collections\/fish-flex\"\u003eFish Flex\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003ch3\u003eStep 3: Prepare the Hospital Tank\u003c\/h3\u003e\n\u003cp\u003eSet up your treatment environment. Transfer the sick fish gently and allow 20–30 minutes for acclimation. Dim the lights to protect the medication from photodegradation.\u003c\/p\u003e\n\n\u003ch3\u003eStep 4: Calculate and Administer the First Dose\u003c\/h3\u003e\n\u003cp\u003eUse one 100 mg capsule per 10 gallons of actual water volume. Dissolve and pour across the surface. Water will turn yellow — expected and harmless.\u003c\/p\u003e\n\n\u003ch3\u003eStep 5: Maintain the Daily Treatment Cycle\u003c\/h3\u003e\n\u003cp\u003eEvery 24 hours: water change, test parameters, add a fresh dose. Maintain consistent temperature and low lighting.\u003c\/p\u003e\n\n\u003ch3\u003eStep 6: Monitor for Improvement\u003c\/h3\u003e\n\u003cp\u003eMost fish show visible improvement within 3 to 5 days. Signs include reduced redness, healing sores, new fin growth, increased activity, and resumed feeding. If no improvement after 5 days, discontinue and consult a veterinarian.\u003c\/p\u003e\n\n\u003ch3\u003eStep 7: Complete the Full Course\u003c\/h3\u003e\n\u003cp\u003eDoxycycline is bacteriostatic — it suppresses growth rather than killing outright. Stopping early lets surviving bacteria resume multiplying with potential resistance. Finish the full 5–10 day course.\u003c\/p\u003e\n\n\u003ch3\u003eStep 8: Post-Treatment Recovery\u003c\/h3\u003e\n\u003cp\u003eReintroduce activated carbon to clear medication and water color. Add aquarium probiotics to restore beneficial bacteria. Monitor fish for 48 hours in the hospital tank before returning to the main display.\u003c\/p\u003e\n\n\u003ch2\u003eSafety, Side Effects, and Precautions\u003c\/h2\u003e\n\n\u003ch3\u003eWater Discoloration\u003c\/h3\u003e\n\u003cp\u003eThe most visible side effect of Fish Doxy is temporary yellow or amber discoloration of the aquarium water. This is caused by the doxycycline itself and is completely harmless to fish. The color clears within 24–48 hours after treatment ends and activated carbon is reintroduced. For this reason alone, treating in a hospital tank is strongly recommended to avoid staining your display.\u003c\/p\u003e\n\n\u003ch3\u003eImpact on Beneficial Bacteria\u003c\/h3\u003e\n\u003cp\u003eAs a broad-spectrum antibiotic, doxycycline can significantly disrupt nitrifying bacteria — more so than targeted antibiotics like cephalexin. Monitor ammonia and nitrite daily during treatment. If ammonia spikes, perform an extra water change and consider dosing bottled nitrifying bacteria. This is another strong reason to treat in a hospital tank rather than your main display.\u003c\/p\u003e\n\n\u003ch3\u003eInvertebrate Sensitivity\u003c\/h3\u003e\n\u003cp\u003eDo not use Fish Doxy in tanks containing shrimp, snails, crabs, or corals. Doxycycline is harmful to invertebrates. Always use a dedicated hospital tank.\u003c\/p\u003e\n\n\u003ch3\u003eLight Sensitivity\u003c\/h3\u003e\n\u003cp\u003eDoxycycline degrades under UV and strong visible light. Keep the treatment tank dimly lit or dark during treatment to maintain the drug's potency. This is unique to Fish Doxy among aquarium antibiotics and important for treatment success.\u003c\/p\u003e\n\n\u003ch3\u003ePotential Side Effects in Fish\u003c\/h3\u003e\n\u003cp\u003eWhen dosed correctly, Fish Doxy is generally well-tolerated. Temporary effects may include reduced appetite, mild lethargy, and hiding behavior during treatment. These typically resolve once the course ends. If severe distress appears — gasping, erratic swimming, excessive mucus — perform an immediate 50% water change and run carbon.\u003c\/p\u003e\n\n\u003ch3\u003eExpired Doxycycline Warning\u003c\/h3\u003e\n\u003cp\u003eUnlike most antibiotics that simply lose potency after expiration, expired tetracyclines (including doxycycline) can potentially become toxic. Always check the expiration date before use and never administer expired Fish Doxy capsules. Dispose of expired medication responsibly.\u003c\/p\u003e\n\n\u003ch3\u003eNot Effective Against Fungal Infections\u003c\/h3\u003e\n\u003cp\u003eFish Doxy targets bacteria. For fungal conditions (cotton-like growths), use a dedicated antifungal like \u003ca href=\"\/collections\/fish-flucon\"\u003eFish Flucon (fluconazole)\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003ch2\u003eStorage and Shelf Life\u003c\/h2\u003e\n\n\u003cp\u003eProper storage is especially important for doxycycline because it is sensitive to light, heat, and moisture. Store capsules in their original sealed container in a cool, dry place away from direct sunlight. Keep the lid tightly closed. Always verify the expiration date before use — expired doxycycline should not be used, as degradation products from tetracycline-class antibiotics can be harmful. Dispose of expired capsules according to local pharmaceutical waste guidelines.\u003c\/p\u003e\n\n\u003ch2\u003eFish Doxy vs. Other Aquarium Antibiotics: Choosing the Right Treatment\u003c\/h2\u003e\n\n\u003cp\u003eFish Doxy fills a unique niche: the broadest single-antibiotic coverage available in the aquarium hobby, with the versatility to handle unclear diagnoses and complex infections. Here is how it compares to the other antibiotics we carry.\u003c\/p\u003e\n\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n\u003cth\u003eProduct\u003c\/th\u003e\n\u003cth\u003eActive Ingredient\u003c\/th\u003e\n\u003cth\u003eDrug Class\u003c\/th\u003e\n\u003cth\u003eBest For\u003c\/th\u003e\n\u003cth\u003eWhen to Choose\u003c\/th\u003e\n\u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003eFish Doxy\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDoxycycline\u003c\/td\u003e\n\u003ctd\u003eTetracycline\u003c\/td\u003e\n      \u003ctd\u003eColumnaris, mixed infections, atypical bacteria, unclear diagnosis\u003c\/td\u003e\n      \u003ctd\u003eWhen the pathogen is unknown, the infection is mixed, or first-line antibiotics have failed\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003ca href=\"\/collections\/fish-mox\"\u003eFish Mox\u003c\/a\u003e\u003c\/td\u003e\n\u003ctd\u003eAmoxicillin\u003c\/td\u003e\n\u003ctd\u003ePenicillin\u003c\/td\u003e\n      \u003ctd\u003eFin rot, ulcers, dropsy, gill disease\u003c\/td\u003e\n      \u003ctd\u003eFirst-line broad-spectrum choice for most general bacterial infections\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003ca href=\"\/collections\/fish-flex\"\u003eFish Flex\u003c\/a\u003e\u003c\/td\u003e\n\u003ctd\u003eCephalexin\u003c\/td\u003e\n\u003ctd\u003eCephalosporin\u003c\/td\u003e\n      \u003ctd\u003eGram-positive skin and fin infections\u003c\/td\u003e\n      \u003ctd\u003eTargeted treatment with minimal tank ecology disruption\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003ca href=\"\/collections\/fish-zithro\"\u003eFish Zithro\u003c\/a\u003e\u003c\/td\u003e\n\u003ctd\u003eAzithromycin\u003c\/td\u003e\n\u003ctd\u003eMacrolide\u003c\/td\u003e\n      \u003ctd\u003eResistant infections, columnaris, atypical bacteria\u003c\/td\u003e\n      \u003ctd\u003eSecond-line option for stubborn or recurring infections\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003ca href=\"\/collections\/fish-flox\"\u003eFish Flox\u003c\/a\u003e\u003c\/td\u003e\n\u003ctd\u003eCiprofloxacin\u003c\/td\u003e\n\u003ctd\u003eFluoroquinolone\u003c\/td\u003e\n      \u003ctd\u003eSevere gram-negative septicemia\u003c\/td\u003e\n      \u003ctd\u003eHeavy-duty option for aggressive systemic gram-negative infections\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003ca href=\"\/collections\/fish-zole\"\u003eFish Zole\u003c\/a\u003e\u003c\/td\u003e\n\u003ctd\u003eMetronidazole\u003c\/td\u003e\n\u003ctd\u003eNitroimidazole\u003c\/td\u003e\n      \u003ctd\u003eAnaerobic bacteria, hole-in-head, bloat\u003c\/td\u003e\n      \u003ctd\u003eAnaerobic infections and protozoa; combinable with other antibiotics\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003cp\u003e\u003cstrong\u003eOur recommendation:\u003c\/strong\u003e For most clear-cut bacterial infections, start with \u003ca href=\"\/collections\/fish-mox\"\u003eFish Mox (amoxicillin)\u003c\/a\u003e as the first-line choice. When the diagnosis is unclear, the infection involves mixed pathogens, columnaris is suspected, or first-line treatments have failed, Fish Doxy's unmatched breadth of coverage makes it the strongest all-around option. For confirmed severe gram-negative septicemia, consider \u003ca href=\"\/collections\/fish-flox\"\u003eFish Flox (ciprofloxacin)\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003ch2\u003eCompatibility and Drug Interactions\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFish Doxy + Metronidazole (Fish Zole):\u003c\/strong\u003e A commonly used and generally safe combination. Doxycycline covers aerobic bacteria while metronidazole addresses anaerobes and protozoa. Many aquatic veterinarians recommend this pairing for complex infections.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFish Doxy + Fish Mox or Fish Flex:\u003c\/strong\u003e Not recommended simultaneously. Use one antibiotic, complete the course, then reassess. Combining broad-spectrum doxycycline with another antibiotic significantly increases the risk to beneficial bacteria.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFish Doxy + Aquarium Salt:\u003c\/strong\u003e Compatible. Low-dose salt (1 tablespoon per 5 gallons) supports osmoregulation without interfering with doxycycline.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFish Doxy + Water Conditioners:\u003c\/strong\u003e Standard dechlorinators are safe. Avoid conditioners with herbal extracts or tea tree oil.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFish Doxy + Anti-Parasitic or Anti-Fungal Medications:\u003c\/strong\u003e Do not combine. Treat one condition at a time.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFish Doxy + Calcium-Rich Supplements:\u003c\/strong\u003e While doxycycline resists calcium binding better than older tetracyclines, avoid adding calcium supplements or mineral blocks during treatment to maximize potency.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eSigns of Recovery and When to Seek Veterinary Help\u003c\/h2\u003e\n\n\u003ch3\u003eWhat Recovery Looks Like\u003c\/h3\u003e\n\u003cp\u003eMost fish show meaningful improvement within 3 to 5 days of starting Fish Doxy. Positive signs include increased swimming activity and appetite, reduced redness, swelling, and streaking, new translucent fin growth at previously eroded edges, healing of skin lesions and ulcers, normalized breathing and gill movement, and clearer body coloration.\u003c\/p\u003e\n\n\u003ch3\u003eWhen to Seek Professional Help\u003c\/h3\u003e\n\u003cp\u003eConsult an aquatic veterinarian if no improvement appears after 5 days, the fish worsens during treatment, multiple fish become sick simultaneously, you suspect a chronic mycobacterial or viral condition, or the problem recurs after completing a full course. The \u003ca href=\"https:\/\/www.avma.org\/resources-tools\/find-veterinarian\" target=\"_blank\" rel=\"noopener\"\u003eAmerican Veterinary Medical Association (AVMA)\u003c\/a\u003e and the \u003ca href=\"https:\/\/www.merckvetmanual.com\/exotic-and-laboratory-animals\/fish\" target=\"_blank\" rel=\"noopener\"\u003eMerck Veterinary Manual\u003c\/a\u003e are trusted resources for finding qualified aquatic professionals.\u003c\/p\u003e\n\n\u003ch2\u003eBrand Spotlight: Trusted Fish Doxy Sources\u003c\/h2\u003e\n\n\u003ch3\u003eThomas Labs \/ Bird Biotic (Legacy)\u003c\/h3\u003e\n\u003cp\u003eThomas Labs popularized the Fish Doxy name alongside its Bird Biotic doxycycline products. These set the quality standard for aquarium and avian doxycycline products for years. While Thomas Labs has ceased production, the brand names remain widely recognized.\u003c\/p\u003e\n\n\u003ch3\u003eAqua Soma Labs (Fix Doxy)\u003c\/h3\u003e\n\u003cp\u003eAqua Soma Labs produces Fix Doxy — the modern successor containing the same pharmaceutical-grade doxycycline hyclate at the same 100 mg strength. Distributed by Fine PetHealth Group, Fix Doxy provides reliable supply with fresh expiration dates.\u003c\/p\u003e\n\n\u003ch3\u003eQuality Indicators to Look For\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eUSP-grade (United States Pharmacopeia) doxycycline hyclate\u003c\/li\u003e\n  \u003cli\u003eClearly labeled strength and capsule count\u003c\/li\u003e\n  \u003cli\u003eVerifiable manufacturer or distributor contact information\u003c\/li\u003e\n  \u003cli\u003eFresh expiration dates — especially important for doxycycline, which should never be used past expiration\u003c\/li\u003e\n  \u003cli\u003eMade in the USA under pharmaceutical-grade manufacturing conditions\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eRegulations and Legal Considerations\u003c\/h2\u003e\n\n\u003cp\u003eIn the United States, antibiotics marketed for ornamental fish — including doxycycline products like Fish Doxy — are sold over-the-counter without a prescription. They fall outside the direct regulatory scope of the FDA Center for Veterinary Medicine and USDA that governs food-animal medications.\u003c\/p\u003e\n\n\u003cp\u003eResponsible use is essential. Doxycycline's exceptionally broad spectrum makes it a powerful tool, but power demands discipline: correct diagnosis, proper dosing, completed treatment courses, and avoiding use when simpler antibiotics would suffice. These practices help preserve doxycycline's effectiveness and minimize the development of resistant bacteria.\u003c\/p\u003e\n\n\u003cp\u003eInternational regulations vary. The European Union, Australia, and Canada generally require veterinary prescriptions for tetracycline-class antibiotics. Verify local regulations before purchasing or importing.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions About Fish Doxy\u003c\/h2\u003e\n\n\u003ch3\u003eWhat is the correct dosage of Fish Doxy for aquarium fish?\u003c\/h3\u003e\n\u003cp\u003eDissolve the contents of one 100 mg capsule per 10 gallons of actual water volume. Repeat every 24 hours for 5 to 10 days, performing a 20–25% water change before each dose.\u003c\/p\u003e\n\n\u003ch3\u003eIs Fish Doxy safe for freshwater and saltwater aquariums?\u003c\/h3\u003e\n\u003cp\u003eYes. Doxycycline is not deactivated by calcium like older tetracycline hydrochloride, making it effective in both freshwater and saltwater. This is one of its key advantages over other tetracycline-class products. Always treat in a hospital tank when your marine system contains invertebrates.\u003c\/p\u003e\n\n\u003ch3\u003eWill Fish Doxy turn my water yellow?\u003c\/h3\u003e\n\u003cp\u003eYes. Doxycycline produces a temporary yellow or amber tint in aquarium water. This is completely harmless and clears once treatment ends and activated carbon is restored. Using a hospital tank keeps the discoloration out of your display.\u003c\/p\u003e\n\n\u003ch3\u003eWhat is the difference between Fish Doxy and Fish Mox?\u003c\/h3\u003e\n\u003cp\u003e\u003ca href=\"\/collections\/fish-mox\"\u003eFish Mox\u003c\/a\u003e contains amoxicillin (penicillin class, bactericidal) and is the standard first-line treatment for most bacterial infections. Fish Doxy contains doxycycline (tetracycline class, bacteriostatic) with broader coverage including atypical bacteria. Choose Fish Doxy when the diagnosis is unclear, the infection is mixed, or amoxicillin has failed.\u003c\/p\u003e\n\n\u003ch3\u003eCan Fish Doxy treat columnaris?\u003c\/h3\u003e\n\u003cp\u003eYes. Doxycycline is widely regarded as the most effective tetracycline for columnaris (\u003cem\u003eFlavobacterium columnare\u003c\/em\u003e). It is often a first-choice treatment for this aggressive disease.\u003c\/p\u003e\n\n\u003ch3\u003eDoes Fish Doxy harm beneficial bacteria?\u003c\/h3\u003e\n\u003cp\u003eYes, more so than targeted antibiotics like \u003ca href=\"\/collections\/fish-flex\"\u003eFish Flex (cephalexin)\u003c\/a\u003e. Monitor ammonia and nitrite daily and treat in a hospital tank whenever possible to protect your main display's nitrogen cycle.\u003c\/p\u003e\n\n\u003ch3\u003eCan I mix Fish Doxy with food?\u003c\/h3\u003e\n\u003cp\u003eYes. For internal infections, crush the capsule powder into gel food, soaked pellets, or frozen bloodworms. Feed once daily for 5–10 days.\u003c\/p\u003e\n\n\u003ch3\u003eShould I dim the lights during Fish Doxy treatment?\u003c\/h3\u003e\n\u003cp\u003eYes. Doxycycline is photosensitive and degrades under UV and strong visible light. Keep the treatment tank dimly lit or dark to maintain the drug's potency throughout the course.\u003c\/p\u003e\n\n\u003ch3\u003eCan I use expired Fish Doxy?\u003c\/h3\u003e\n\u003cp\u003eNo. Unlike most antibiotics that simply lose potency, expired tetracyclines can become harmful. Always check the expiration date and dispose of expired capsules responsibly.\u003c\/p\u003e\n\n\u003ch3\u003eCan Fish Doxy treat fungal infections?\u003c\/h3\u003e\n\u003cp\u003eNo. Doxycycline targets bacteria only. For fungal conditions, use \u003ca href=\"\/collections\/fish-flucon\"\u003eFish Flucon (fluconazole)\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003ch3\u003eWhat should I do if Fish Doxy does not work?\u003c\/h3\u003e\n\u003cp\u003eIf no improvement after 5 days of correct dosing, discontinue and consult an aquatic veterinarian. Consider escalating to \u003ca href=\"\/collections\/fish-flox\"\u003eFish Flox (ciprofloxacin)\u003c\/a\u003e for gram-negative infections, or \u003ca href=\"\/collections\/fish-zithro\"\u003eFish Zithro (azithromycin)\u003c\/a\u003e for resistant strains.\u003c\/p\u003e\n\n\u003ch3\u003eDo I need a prescription to buy Fish Doxy?\u003c\/h3\u003e\n\u003cp\u003eNo. Fish Doxy is available over-the-counter for ornamental fish use in the United States. No prescription required. We ship fast with multiple delivery options.\u003c\/p\u003e\n\n\u003ch2\u003eConclusion\u003c\/h2\u003e\n\n\u003cp\u003eFish Doxy occupies a unique and essential position in the aquarium antibiotic lineup: it is the broadest-spectrum single antibiotic available to hobbyists, capable of reaching gram-positive, gram-negative, and atypical intracellular pathogens that no other common aquarium medication can touch. Its tetracycline-class mechanism, lipid-soluble tissue penetration, resistance to calcium deactivation, and anti-inflammatory properties make it the go-to choice when infections are complex, unclear, or unresponsive to standard first-line treatments.\u003c\/p\u003e\n\n\u003cp\u003eUsed responsibly — with accurate diagnosis when possible, proper dosing, full treatment courses, dimmed lighting, and hospital tank isolation — Fish Doxy gives your ornamental fish a powerful path to recovery even in the most challenging cases. Keep it in your fishkeeping first-aid kit alongside \u003ca href=\"\/collections\/fish-mox\"\u003eFish Mox\u003c\/a\u003e and \u003ca href=\"\/collections\/fish-flex\"\u003eFish Flex\u003c\/a\u003e, and you will be prepared for virtually any bacterial emergency your aquarium throws at you.\u003c\/p\u003e\n\n\u003cp\u003eReady to treat? \u003cstrong\u003e\u003ca href=\"\/collections\/fish-doxy\"\u003eShop Fish Doxy (Doxycycline) Capsules\u003c\/a\u003e\u003c\/strong\u003e — 100 mg, available in 30-count and 60-count bottles, in stock, no prescription required, with fast shipping.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch3\u003eRelated Products\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003ca href=\"\/collections\/fish-mox\"\u003eFish Mox (Amoxicillin) Capsules\u003c\/a\u003e — First-line broad-spectrum antibiotic for general bacterial infections\u003c\/li\u003e\n  \u003cli\u003e\n\u003ca href=\"\/collections\/fish-flex\"\u003eFish Flex (Cephalexin) Capsules\u003c\/a\u003e — Targeted gram-positive treatment for fin and skin infections\u003c\/li\u003e\n  \u003cli\u003e\n\u003ca href=\"\/collections\/fish-zithro\"\u003eFish Zithro (Azithromycin) Tablets\u003c\/a\u003e — Macrolide antibiotic for resistant and atypical infections\u003c\/li\u003e\n  \u003cli\u003e\n\u003ca href=\"\/collections\/fish-flox\"\u003eFish Flox (Ciprofloxacin) Tablets\u003c\/a\u003e — Heavy-duty treatment for severe gram-negative septicemia\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eExternal Resources\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\u003ca href=\"https:\/\/www.avma.org\/resources-tools\/find-veterinarian\" target=\"_blank\" rel=\"noopener\"\u003eAmerican Veterinary Medical Association (AVMA) — Find a Veterinarian\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"https:\/\/www.merckvetmanual.com\/exotic-and-laboratory-animals\/fish\" target=\"_blank\" rel=\"noopener\"\u003eMerck Veterinary Manual — Fish Health\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"https:\/\/www.fda.gov\/animal-veterinary\" target=\"_blank\" rel=\"noopener\"\u003eFDA Center for Veterinary Medicine\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\u003cem\u003eDisclaimer: This article is for educational purposes only and does not constitute veterinary advice. Fish Doxy and all products discussed are intended exclusively for ornamental and aquarium fish. They are not for human consumption or for use in food-producing animals. Consult a qualified aquatic veterinarian for diagnosis and treatment recommendations.\u003c\/em\u003e\u003c\/p\u003e","brand":"Fish Mox Supply","offers":[{"title":"30 Count","offer_id":44556808683655,"sku":"FD-100-30","price":44.99,"currency_code":"USD","in_stock":true},{"title":"60 Count","offer_id":44556808716423,"sku":"FD-100-60","price":80.99,"currency_code":"USD","in_stock":true},{"title":"100 Count","offer_id":44556808749191,"sku":"FD-100-100","price":93.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0361\/8173\/7607\/files\/fish-doxy-doxycycline-100mg-30ct-front.webp?v=1777842161","url":"https:\/\/fishmoxsupply.com\/products\/fish-dox-100mg-30-tablets","provider":"Fish Mox Supply","version":"1.0","type":"link"}