I've had a change of light tube about 3 weeks ago and a change of location. There is filtered daylight in this room, although none on the tank directly. Slowly the brown algae and scum has come back. The oto aren't really cleaning it up though I can see them trying. The latest concern is that the twisted val has gone a bronzey colour. The anubias and the crypts are still ok, most plants have a perfect new leaf at present. The balansae is making a comeback.
In the CPD tank there is a lot of the scum, it looks like the tank needs a serious dusting and a few cobwebs removed. This tank doesn't seem to get the brown algae.
Both of these tanks are next to each other in the new room, do you think this is all caused by increased light?