Cloudy water in the AM then clear - why?

[specwar]

Hey Group. I'm getting back into the hobby after being away for decades. Here is my question. Why does my tank water seem a little cloudy in the morning when the lights go on and then it clears up as the day goes on? It has never happened in my 13.5 Nano but only on my main 37.5 Tall. Thanks

 

[LesPoissons]

what do you have in the tank? do you have any sand sifters that are more active at night? do your power heads go on a different schedule at night?

 

[specwar]

what do you have in the tank? do you have any sand sifters that are more active at night? do your power heads go on a different schedule at night?

Just a Chromis that went in 3 days ago. I set it up 6 weeks ago. 20 lbs of live sand. 25 lbs of LR. No changes in filter time/powerheads etc. No CUC yet