Male Platy Always Hiding Around The Bottom Of The Tank

[KrystenM]

I've had two Platies for about a month now and all was good. My female actually just died yesterday from getting stuck in a VERY small "window" in one of my decorations.

Very sad.  I've gradually been adding some fish once in a while such as a dwarf gourami, a honey gourami, a cory, and some  My male has been acting different the past week. He always seems to be hiding, whereas he used to always be with my female platy. If he's not hiding, he's outside but always on the bottom of the tank. Also, it seems that his fins are a bit clamped, and he looks as if he's breathing quite quickly/heavily. He acts normal when I feed my fish. The Dwarf Gourami can be a little intimidating at times. What could be wrong? All my other fish are perfectly fine!
 
Tank size: 12 gallons
Nitrate: 20 ppm
Nitrite: 5.0 ppm
Hardness: 300
chlorine: 0
alkalinity: 80 ppm
pH: 7.2
 
P.s. I realize my nitrites are far too high. I'm cleaning my filter and tank today, and I think I know why it's suddenly gotten so high, so  don't worry I'm not oblivious to that, but could this be the reason he's acting like this?

 

[hudsona85]

Sorry to hear about your fish loss. How long has it been since your tank was cycled? Another good thing to test for is ammonia. Ammonia is very toxic to fish. This might be the cause of platies dying. I would recommend not cleaning the filter and the tank at the same time. Doing these at separate times will keep good bacteria in the tank and prevent situations like these from coming up less often. I am not sure but can confidently say you might have too small of a tank to house some of these fish. Gourami need their space especially when it comes to having another male in the tank. Even then there will be some quarrels. Cory cats also do better in a shoal of at least 6.

 

[AmtotheBurr]

Your nitrite should be reading zero as well

 

[Ltygress]

To put it VERY short, sweet, and simple...

Yes, the high nitrites could be why he's acting like that. And without knowing how long they have been that way, or how bad he is acting/looking, it MAY be irreversible damage.

 

[Byron]

If the nitrite number really is 5 ppm, it is miraculous the fish are even alive.  Nitrite at 0.25 ppm will affect fish, and above 0.5 they usually have serious difficulty with death following shortly.
 
Aside from the initial cycling, two months now, which may have been OK, the 12 gallon tank is insufficient space for all these fish, and I would suspect this is the cause of the nitrite issue.  Ammonia is probably high also, another toxin.  The choice of fish is going to be very problematic too, at some point, and you may be seeing signs of it now.  The dwarf gourami can be territorial, and in so small a space this only intensifies his aggression.  The Honey should not be combined with the dwarf, and aside from this the space issue again.  There is no room for a group of corys, they must have five or six minimum.  I don't know what else may be included, you didn't finish that sentence in post #1.
 
Byron.