Fish & shrimp health
What's wrong with your fish or shrimp?
Salt-like spots, ragged fins, a gold dusting, a shrimp stuck in its shell. Each points somewhere different. Find the match below, then treat it the planted-tank way, without copper or harsh meds that wipe out your shrimp, snails and beneficial bacteria.
Fish diseases
Most fish illness is a parasite, a bacterial infection, or a fungus taking hold on a stressed or injured fish. Match the look to the cause, then treat without harming your inverts and plants.
- Ich (White Spot)ParasiteGrains of white salt scattered over the fins and body, and fish flicking against surfaces.
- Fin RotBacterialFin edges going ragged, milky or red, eating inward toward the body.
- Velvet (Gold Dust Disease)ParasiteA fine gold or rust-coloured dusting over the skin, best seen with a torch held at an angle.
- Columnaris (Cotton Mouth)BacterialWhite or grey cottony patches around the mouth and body, and greyish saddle marks, spreading fast.
- DropsyBacterialA swollen belly with scales sticking out like a pinecone, often with bulging eyes.
- Fungal InfectionFungalFluffy, cotton-wool tufts, usually white or grey, on an injury, the mouth, or on eggs.
- Swim Bladder DisorderEnvironmentalA fish floating at the top, sinking to the bottom, or swimming sideways or upside down.
- Hole in the Head (HLLE)OtherSmall pits or eroded holes on the head and along the lateral line, mostly on cichlids.
Shrimp problems
Shrimp rarely 'catch' things the way fish do. Their troubles are mostly water chemistry and molting, plus a couple of treatable external hitchhikers. Internal infections are best prevented, not cured.
- Shrimp Molting ProblemsEnvironmentalA shrimp stuck half-out of its old shell, or dead with a distinct white ring around the middle.
- Shrimp Bacterial InfectionBacterialA pink or orange tint deep inside the body (as if partly cooked), or sores and dark spots on the shell.
- Vorticella & Scutariella (Shrimp Parasites)ParasiteWhite fuzzy or thread-like growths on the shrimp's nose, head or shell, sometimes waving in the flow.
A sick fish or shrimp is nearly always telling you something about the tank: a chill, a water-quality slip, a stressed newcomer, or minerals out of range. Match the symptom, treat the animal, then fix the cause so it doesn’t return. Every guide flags which treatments are safe around shrimp, snails and plants, and which belong in a quarantine tank. If it’s the plants that look unwell rather than the animals, see plant deficiency ID.