Attack or disease

[Staffylover]

Hi There,
Any amount of Ammonia in your water is not good, it is toxic to fish, this should be 0, check you are reading the colour correctly by also taking a sample from your tap, if there is ammonia present I would suggest a minimum 50% water change
Nitrite should also read 0,
Nitrate is unlikely to be 0 this is the end product of the micro munchers in your filter that convert toxic ammonia and nitrite into nitrate,(nitrogen cycle) perhaps run that test again?
If your filter is not coping with the amount of fishy waste this is why you would be getting ammonia readings, water changes will be needed to help the filter out,
Regarding the fish it's hard to tell from the photo it could be a tumour perhaps? just a guess really, it looks a bit severe so there may not be much you can do sadly.

[plankton]

Give the bottles that test the nitrate a damn good bashing on a table to make sure they're well mixed.
My nitrate reads close to zero from the tap, so it does tend to look like zero even from the tank - but test the tap water so you know where your start point is.
Water changes to get rid of any toxins like ammonia and nitrite is necessary as above.

[Xemas712]

Ok thank you I've done a water exchange so that should solve some of it

[FishBubs]

Hi,
Are you adding any water conditioner such as seachem prime (or equivalent) to give her extra protection against any remaining amonia levels?

[Xemas712]

No I am not as normally I leave the water 24 hours before using it

[plankton]

Does your tap water not have any chloromine added to it?
You do need to be careful as these will upset the balance of the tank as well as chlorination.
Check with your supplier.
Seachem Prime is good for help in keeping ammonia and nitrite neutralised as well.

[fr499y]

I would never recommend leaving water out for 24 hours without treatment. Chloramine doesn't off-gas like chlorine does, IIRC it can take something like 5 days depending on the amount. As above, get some Seachem Prime and treat the water/tank.

[Xemas712]

Ok il get on it thanks for the advice