Hi, im new to site, just registered.Just built my own diy alga scrubber for my 50 gallon freshwater tank.Its week 3 now with diy project had to make a few modifications but now growing alga turf.Decided to build scrubber because alga growth in tank as been a pain.Had to clean aquarium glass every four days,tried everything to correct problem with no joy thats why ive built the scrubber.I know what problem is too much light, keep fish in conservatory ,asking for problems and tank is open top type which allows even more light.Fingers crossed this scrubber will sort.