Skimmer has me confused

[riche]

I tune my skimmer and it’s working great but as soon as the lights go off on the tank the skimmer “slows down” and the bubbles don’t even fill the neck

It’s a Reef octopus 110 classic

It was doing it when I had the bubbles magnus curve 5 on the tank previously

That’s the only thing that is different, the lights are off.

Help me make sense of this

 

[Pntbll687]

Maybe a bacteria in the water that is photosynthetic or an algae. Then when the lights go out, it stops reproducing, and the skimmer would have less to pull out.