Algae Detachment

How many days did you let it grow before that started happening?

 

You will want to do that palm swipe at least every 14 days, you don't want to allow any unwanted algae to remain on the screen for very long. You can actually do that palm-swipe a couple times a week. If you didn't touch the screen for 30+ days, I think that would explain why you had that detachment.

 

That could be oxygen production getting trapped in a pocket. It's kind of odd how that can happen but I've seen it more than once.

What I would do is just shut off the flow and allow the algae mat to flatten out a couple times a week. You could also take it out and give it a palm-swipe & rinse a couple times a week. I suppose you could have an area of the screen with very little growth, so there's nothing to prevent an air pocket from forming, and the pocket forming prevents growth from filling in at that area of the screen, so it's a vicious circle. Once it fills in, you shouldn't have that issue anymore.

Just a theory on that whole vicious circle thing...but it kind of makes sense