Concerned fish dad, zebra danio not moving.

[Jblair21]

So I am cycling a 125-gallon tank with 4 zebrafish and one of them is not doing fine. He was hiding in a ship ornament for a few days and now he is behind a plant almost immobile and laying on the gravel but still breathing he hasn't been eating in 3-4 days now. My water parameters are:
Ammonia: 0.20
Nitrite: 0
Nitrate: 0
pH: 7.5
Temp: 77 F

I don't know what to do! The other 3 zebrafish are fine and playing with each other, I thought about adding more but I am concerned it could affect my cycle and the other fish in the tank, any advice is appreciated.

 

[Noroomforshoe]

I would humanly euthinize that fish. The dead fish can be used to complete your cycle, it is actually a bigger sorce of ammonia then the live fish. You could stuff it in a nylon stoking and hang it over the edge of the tank, you will get the benifit of the ammonia without the mess. I suggest you add 3 or 4 grocery store shrimp to the nylon as well, 4 danios in a 125 is going to take forever to cycle.

If you use clove oil to euthinize your fish "You should" DO NOT put the dead fish back in the tank!

 

[Kitley]

I cycled my 75 gallon with 4 zebra danios and all went smoothly. Pretty sure you could add more for the cycle. but maybe if you put the dead fish in, you wont need more for the cycle.

 

[MrsPancakes]

It sounds like your guy is past the point of return. I would humanely euthanize with clove oil (as suggested above). Although we do our best, sometimes our fishy friends die for whatever reason.
Just a tip: You will need to add at least three more danios to the mix, and your temp is at the highest it can be for them. Also, they prefer to be in groups of six or more. They can get nippy otherwise. I have 28 longfins in my main tank. A big school of these guys is fun to watch.

 

[Jblair21]

Thanks, the little guy did not make it through my 3 hour nap. I feel bad and wish i euthanized him when i noticed the strange behavior but didnt want to act prematurely. I will take the combined advice and add some more as well as cycle with the dead fish and some shrimp. Atleast his death will contribute to the wellbeing of the rest of the tanks life. Thanks everyone