How do clownfish sleep?

[realtek]

Hello,

I purchased 2 small clownfish 3 days ago and when I woke up this morning 1 was
swimming around the surface like it was sick and the other one was laying underneith a rock.

I was getting ready to do a quck water change, I went away for about 2 minutes.... came back
and they were swimming very happy as if nothing had ever happend.

Can anyone explain this? or at least advise me if this is normal?

 

[JasonF]

Well I have only had Clowns for a few days in my tank, and when I came down in the morning I thought they were both dead, they looked like they were floating in the corner of the tank... After the lights went on they perked up.. One night I came down at 4am to check on them too.... They again looked dead/doped, but perked up once the lights are on, so I guess they are heavy sleepers...

 

[Gomer]

Are you peoples tanks Cycled? You could be having ammonia or nitrite spikes which can be deadly to fish.

Do you have the right amount of salt in the tank?

These are normally beginner things, but since you both have <10 posts, it might apply.

 

[JasonF]

I am not convinced the Aragonite I got was suitable or even did anything let alone complete the cycle quickly so despite having low/zero readings they suddenly began to climb, so I took the fish to the fish shop and they are looking after them for me.

The tank appears to be cycling now, but it appears to be stuck with Nitrites at 2ppm, has been for 5 days now. I guess it took the fish to start it properly and the aragonite did sweet FA, so that was an expensive substrate..