A few more things. Change out your activated carbon to help reduce your dissolved organic carbon levels. If you can add a skimmer, that will help too. If you are not already doing weekly water changes, you need to start. Finally, make sure your alkalinity is where it needs to be.

Dosing with Chemi-Clean is a short term solution, but it will come back. The root cause needs to be addressed. The cause is high organic levels, low circulation, and detritus buildup. As always, nuisance algae problems are usually and indication of other problems with water quality.

I'm not quite sure how cutting back lights improves water quality, but I'd like to hear it.