You most probably know as much as me (or more) on algae, I have been through the same battles as you. One of the things I found effective was to reduce my lighting from 12 to 9 hours, suddenly the algae did not want to know. I do not have as much light as you (2 watts per gallon) but it might be worth a try.
I know you are on 10 hours a day so you are not much different to me, however some people run on 6 or 7 hours so you could try that as an option.
Sorry cannot be more constructive
