I have three male guppies in my 60L tank. Two appear fine, swimming all over the tank.
I've had these for about 6 months now.
Those two do whoever occasionally like to sleep on the bottom of the tank.
The third one, rarely moves. For the past month he mostly stays almost still at the top of the tank. He appears to look ok. He does not appear to be gasping for anything. Just appears lathargic
I have four marina coloured LED
lights in the tank. These only get switched on in the evenings, during the day, I use the main light on the tank. In the last week, he has taken to just resting on the top of the lights during the day.
At feeding time, he comes out and eats. Swims about for a bit and then goes back to above the lights or to the top of the tank.
I'm taking daily water readings at the moment (as opposed to my normal twice weekly ones), and I have changed the water twice in the last week as a percaution. Ammonia levels are less than 0.25 (more yellow than yellow green), Nitrites are 0, Nitrates never get above 5. Temperature is 76 degrees. PH is 7.4.
I'm starting to worry about him. Any ideas / tips.