about a month ago I built a Waterfall Scrubber thats 18cm wide, with 1100 l/h flow. it has been growing good brownish/green algae but about 4 days after cleaning white patches start to appear all over the screen.
Is this bad and if so what could be causing it?
oh and I have an 18watt warm white energy saver that is about 5 cm away from the screen with a reflector