Pet Health Library

Guides to pet symptoms and conditions, cited to the veterinary literature — what's normal, what's not, and when to see a vet.

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Showing 1–9 of 9 articles found

🐟Fish HealthJul 26, 2026

👁️Eyes & Ears

Betta Popeye (Exophthalmia): Causes, Treatment, and Recovery

One or both of your betta's eyes suddenly bulging is popeye — a sign, not a disease on its own. Here's what causes it, why clean water is the real cure, and when to call an aquatic vet.

🐟Fish HealthJul 25, 2026

Betta Fish Fungus: White Fuzz, Cotton Mouth, and How to Treat It

White, cotton-like fuzz on a betta is usually one of two very different problems — true water-mold fungus (Saprolegnia) or columnaris, a bacterium that only looks fungal. Here's how to tell them apart, why the difference flips the treatment, and how to fix the water and temperature that let it start.

🐟Fish HealthJul 22, 2026

Goldfish Fungus: Cotton Wool Disease vs. Columnaris

The white cotton-wool fluff on a goldfish is usually one of two look-alike problems: Saprolegnia water mold (true fungus) or columnaris, a bacterium that only looks fungal. Here's how to tell them apart, fix the water first, and know when to call an aquatic vet.

🐟Fish HealthJul 21, 2026

Betta Swim Bladder Problems: Floating, Sinking, and Listing to One Side

Your betta is floating, sinking, or tipping sideways. "Swim bladder disease" is a sign, not a diagnosis — and bettas differ from goldfish in ways that change the fix. What to check first, what actually has veterinary backing, and when to call an aquatic vet.

🐟Fish HealthJul 18, 2026

Goldfish Dropsy: Why the "Pinecone" Look Is a Warning Sign, Not a Disease

Dropsy in goldfish isn't an illness you treat directly — it's fluid buildup that signals a serious internal problem. Here's how to recognize pineconing, tell it apart from bloating or a swim bladder issue, what to do first, and the honest prognosis.

🐟Fish HealthJul 17, 2026

🍽️Eating & Drinking

Betta Fish Not Eating? Causes and What to Do

A betta that skips meals is usually reacting to its water, not its food. Here are the most common reasons bettas stop eating — cold water, ammonia, overfeeding, stress, and illness — plus simple steps to get your fish eating again.

🐟Fish HealthJul 16, 2026

🐛Parasites

Goldfish Ich (White Spot Disease): How to Spot It and Treat It Safely

Ich, or white spot disease, is a common goldfish parasite that looks like grains of salt. Here's how to recognize it, why the life cycle dictates treatment, how to clear the whole tank, and when gill involvement becomes an emergency.

🐟Fish HealthJul 15, 2026

🌿Skin & Coat

Betta Fin Rot: Why It Happens and How to Heal Your Betta's Fins

Fin rot in bettas is almost always a sign of poor water quality, not bad luck. Here's how to spot it early, fix the tank first, and know when medication or an aquatic vet is needed.

🐟Fish HealthJul 14, 2026

🤮Digestive

Goldfish Swim Bladder Disorder: Why Your Fish Floats, Sinks, or Tips Over

If your goldfish is floating upside down, listing sideways, or stuck on the bottom, swim bladder disorder is usually a sign of a water-quality or feeding problem — not a single disease. Here's how to find the real cause, what to do first, and when to call an aquatic vet.