sick fish

[the_taxidermist]

I have 4 discus about 2.5 to 3 inches that have been in quarantine for around 9 weeks.
All was fine yesterday, tonight one is in distress.

The ailing fish has a very swollen belly, and is having trouble remaining upright when swimming.
We have gotten colder here, and I noticed that tank temp has dropped from 82/83 to 76/77over the last few days, have adjusted heater.
Also recently fed API pellets for the first time, but they do not seem interested in eating them.
Diet is frozen bloodworms in morning, pellets midday and tetra flake in evening.
Do a 50% water change weekly, most recently saturday, then again tonight when I discovered sick fish.
Set up is 20 gallon bare tank with heater and sponge filter and large airstone

I would appreciate any help!!

[Phillydubs]

Im surprised it is only 1 fish that shows an issue...

50% once a week with 3 feedings a day and 4 fish in a small 20 gallon is a recipe for disaster my friend... The water changes you are doing aren't even sufficient for daily changes let alone weekly!

You want to start doing 75%-100% daily and make sure you get all uneaten food out. If you are adding pellets and they dont eat them and they sit there for a week you are basically poisoning them.

What is your plan with them? Are they going to a bigger tank with other fish...

I'd start with big daily water changes maybe even twice a day and make sure the temp stays stable. Sounds like there may be some bloat going on so you could add some epsom or aquarium salt to try and help that fish pass the blockage

[the_taxidermist]

Fish appears to be fine this morning after last nights water change, belly swelling gone and swimming normally!
These fish are due to go into 46 gal tank (that currently house one 6" female discus) in a couple weeks.
I believe I will stop feeding the API pellets in either tank; they do not seem to be eating any of them!
There seems to be some confusion over recommended water changes?
Whenever the subject comes up, some tell me 50% once a week, some say that is too much?
That is for the 46 gal, more for the small tank?
Changes are tap water, less than 2 degree variation

[Phillydubs]

You may want to read the stickies here and watch some stuff on basic discus care...

50% once a week is not going to do well

[Ryan925]

Fish appears to be fine this morning after last nights water change, belly swelling gone and swimming normally!
These fish are due to go into 46 gal tank (that currently house one 6" female discus) in a couple weeks.
I believe I will stop feeding the API pellets in either tank; they do not seem to be eating any of them!
There seems to be some confusion over recommended water changes?
Whenever the subject comes up, some tell me 50% once a week, some say that is too much?
That is for the 46 gal, more for the small tank?
Changes are tap water, less than 2 degree variation

Anyone that tells you a wc is too much doesn't know discus. You can never do too many wcs but you definitely are doing too few