my fantail had pink patches on its white body and is being very quite and hiding behind the filter , any suggestion on whats wrong ?
thanks x

could you perhaps post more details about the fish and tank? it would help us to know the following details:

size of tank:
size of fish:
how many fish are in tank:
filtered: (edit: sorry, you mention filter in the question, so im guessing the tank is filtered XD)
how long has the tank been set up:
was the tank cycled before you added the fish, if so, how:

also, if you have test results for Ammonia, NitrITE and NitrATE, they would be of great help (if you dont have a testing kit, either get a decent liquid test kit, or take the water someplace for them to test it for you and have them write down the results).

lastly, perhaps a photo of the pink patches would help.

once we know these details, we should be able to have a better undertstanding of whats going on, what they are, and what is causing it.

tank size - around 80 - 100 Litres
fish - small about 4-5cm
7 fish in the tank including this one all the rest are fine
one died a few weeks ago as it has swimblader and another died of unknown cause
tank been set up about 6-7months
sorry 'cycled' ??

yeh a will have the water checked , just didnt think of it being the water as the other fish are fine :Y:

hope this helps a bit x