how do i know if my cycle is done??? its been almost 2 months...it hasntt had algae growing on my rocks at all until the past 2 weeks when brown algae starts to grow on my lr. its jes on the rocks tho and none on the sand...i have 2 aquaclear 50 powerheads in there a wet/dry with bioballs and a skimmer...it is a fowlr tank for now...