Folks, I regret to say I pulled the scrubber from my tank. After a year experiment. I got nothing. Surely it was a flaw in design ,flow. or lighting. My overflows have grown more algae in a year than the scrubber . I'm not giving up on algae scrubbers, just have other things going on and it wasn't practical for me to keep this scrubber up and going. I will return to a scrubber in the future. I want to thank everyone for the advice.
Best Regards, Brian Jackson