My waterfall scrubber currently grows a nice crop of almost black dark green, some hair algae, but mostly stuff that comes off pretty easily when I scrape it. Sometimes with extra yellowish slime here and there. It seems to work fine to reduce Nitrates and Phosphates, but I don't seem to get the hair algae lighter green growth that others seem to get. The scrubber is two sided, with 30 watt red and blue LED lamps - with a pretty decent flow. The lamps are 3 inches from the screen on each side. Light cycle is 20 hours on, 4 off every day. I get lots of algae, but not the luxuriant green growth I have seen in pictures here and on the other site. the screen has been in use for at least 4 months at this point, I would call it mature. Any suggestions? Increase flow? Add Iron?
Is that color as observed under LED light or regular light? When you harvest it and squeeze it, does it look brighter? That's when I judge color - not on the screen generally.
Should be fine. The black stuff is like oil almost, it's so black, and it doesn't really grow per se, it sort of is just a coating and it flakes off.
For any plant to be nice and green ammonia is needed to some extent. The problem is- you should not want it in your tank at all for other well known reasons. I would say that not having bright green screen is actually good sign.
I would say that plants need nitrogen, and ammonia is just one form of that. But ammonia is released into the water either continuously by some corals or in bulk when a fish excretes waste. So while there should never be measurable ammonia, it is still there, it just gets consumed/converted very quickly.
Everytime I find dead snail in my tank , I also find nice green growth on the screen for several days to week. After that growth returns to brownish yellow alien sort and keeps parameters at very low levels. After 3 years of using scrubber I dont care about growth color anymore. Low N and P is what matters for me.
