Slow losses when feeding isn’t crazy
This looks like: infectious disease, internal parasites, or poor individual fish quality
Why this happens
Not every death is your chemistry — columnaris, internal worms, and TB can kill over weeks. Pet-shop fish sometimes arrive compromised.
How sure are we? Moderate — rule out ammonia spikes first if any doubt.
What to do right now
- Photograph skin, fins, and poop — clarity drives the next move more than guesswork.
- Isolate one struggling fish if you can with mature filter fiber and matching temp.
- Test GH/KH if you never have — some species crash on ultra-soft water slowly.
- Pause new purchases; ask the store about recent shipment stress.
- Research symptoms on our species pages before buying meds (ich vs fungus look different).
What not to do
- Don’t shotgun five medications — identify first when possible.
If that doesn’t fix it
If bodies show ulcers or fray threads together, see bacterial columnaris patterns.
Catch this earlier next time — log your water parameters in App-aquatic. Free forever.