Fish Health Guides
Clear, cautious guides to help you identify a problem and understand your options before you buy.
Fin Rot in Fish: Causes, Symptoms and Treatment
Learn how to recognize fin rot, why it starts, and the steps aquarists take: water quality fixes first, then a hospital tank and the right antibiotic class.
Medication guideFish Antibiotics Compared: Which Class Treats What
A side-by-side comparison of the antibiotic classes used in aquariums: penicillins, cephalosporins, fluoroquinolones, tetracyclines, sulfonamides and more.
How-toHow to Set Up a Fish Hospital Tank
A step-by-step guide to building a hospital tank: size, filtration, heater, hiding places, and how to cycle it so medication works safely.
Bacterial infectionsDropsy in Fish: Signs, Causes and Treatment Options
Dropsy makes fish swell with raised, pinecone-like scales. Learn what causes it, how to respond quickly, and which treatments keepers use.
Bacterial infectionsPopeye (Pop-Eye) in Fish: Causes and Treatment
Bulging eyes in fish can come from injury, bacteria or water problems. Learn how to tell them apart and what to do.
DiagnosisColumnaris vs Fungus in Fish: How to Tell the Difference
Cotton-like patches on fish are often columnaris, a bacterial infection, not fungus. Compare the signs and learn how treatment differs.
ParasitesBloat and Internal Parasites in Fish
Swollen bellies, white stringy waste and weight loss can signal internal parasites. Learn the signs and how metronidazole is used.
ParasitesIch and Velvet in Fish: Identification and Treatment
Learn to tell ich from velvet, how their life cycles affect treatment, and why antibiotics will not cure external parasites.
How-toWater Quality During Fish Treatment: What to Test and Change
Medication only works when water conditions support the fish. Learn which parameters to test, how often, and how to manage water changes during treatment.
Medication guideWhat Is Fish Mox? Amoxicillin for Aquarium Fish Explained
Fish Mox is amoxicillin for aquarium fish. Learn what it treats, what it does not, the 250mg and 500mg strengths, and how to use it safely.
Medication guideFish Mox vs Fish Mox Forte: What Is the Difference?
Fish Mox and Fish Mox Forte are both amoxicillin. The difference is the strength per capsule. Compare 250mg and 500mg and see how to choose.
Q&AFish & Bird Medication Questions Answered
Short, clear answers to the most common questions about aquarium fish antibiotics, antiparasitics, antifungals and bird azithromycin, from Fish Mox to hospital tanks.