1st no its not in the res on top of the trays....which i clean constantly
2nd i live in a VERY dry climate the humidity in the room does not get above 30% ever
3rd grow room temp is 80-90 degrees (using 1500ppm co2)
4th i clean the entire system weekly (which is a pain in the ass the res is the easy part) and the entire room between grows.
My question was not how to control algea but whether algea was bad. my other question was can I used TOO MUCH hydroguard
and my third question was do i HAVE to use epsom salt if i am on 3 part gh
so please stick to the question. dont assume i dont know proper humidity lvls or that algea requires sunlight for photosynth...i am plenty aware...thank you