Couple sick fish

[MitcherNeaf]

Hey guys havent posted in a while but everything has been going great with my tank until recently. Just checked my water for amonia,nitrate,nitrite lvls, everything seems good small amt of nitrates like a 10 not very high thats usually where it is. I have a 55 gal with 4 cherry barbs in it, recently 2 of them have been floating to the top and just hanging out there not moving much. Finally today i found 1 of them dead, and can only find one other one. Searched around and cant find the other 2 but they do tend to hide sometimes. I checked lvls after he died so i dont think he effected the water.

Also my bala shark is floating straight up and down or pretty close to that. He can swim normally but then when he stops he floats like that, and on both of his sides there is a whiteish blotch that you can see. Its sort of glossy white, as well the black on his dorsal fin is fading. He doesnt look healthy, could this be some sort of parasite?

Lastly i just bought 2 blue gourami's that were fine for the first couple days and now the one is fine and the other just floats in the corner. The first day i had them they were very active and eating well now the one isnt doing very well. I chased him from the corner and he swam around fine but then once again went right back to it just floating there. So im thinking i got something in this tank. Any ideas of where to start and what to try. Ive never medicated my tank and want to do it right, i trust you guys more than the LFS. Thanks and I am sure my little fish will thankyou too.
Mitch

PS also i havent done a water change as of late, i have been adding water due to the lvl getting low but with the parameters being good and i use an outside water line and its so cold i cant turn it on i havent been doing partial water changes, is this where i should start or should i start medicating, cause this has been going on for maybe 2 weeks now.

 

[Zagz]

What is the temp of your water and do you have an airstone at all?

Is the whitish blotch cottony at all? It may be a fungus.Can you get a pic?

 

[DepotFish]

Sounds like a bacterial issue. Floating can be caused by bacteria doing internal damage. The white splotch can also be bacterial. You should be doing water changes, not just topping off. Is that all you have in the tank? If you are lightly stocked you may get away with treating the tank without having too many cycling troubles, but anti-bacterial treatments do kill off the beneficial bacteria and should ideally be done in a quarentine tank. If I were you, I'd think about quarentining fish from now on before adding them to the main tank.

 

[MitcherNeaf]

Well I did do a water change and found 2 more cherry barbs on the bottom of the tank that i was able to get out. I vacumed and did 50% im going to see how they are doing tomorrow and i will get a picture of the bala cause he is the only one with any physical problems. I have a HOB filter with no air stone. I also have a albino shark, 3 clown loaches, a large pleco, 3 bala sharks 2 med 1 small, 1 cherry barb left (had 4), 2 blue gouramis. Most of the fish are still very small its a new tank and i dont want to overstock for the future. Plan on getting bigger tank soon.

Also i have a 10 gallon tank that i had fish in for my daughter, she got ahold of the fish food and fed the 5 tetras enough food to last them a year, lets say i didnt get home in time to find it.. But that tank should do fine for a quarintine tank. When i get a picture of the bala on and you guys can tell me what you think it is i can use that tank for the sick ones.
Mitch