It looks fine to me. Keep an eye on it to be sure, but it doesn't look like anything bad to me.my plants are healthy as can be, i use advanced nutrients and additives could this be benificial fungi or do i have somthing to worry about here?
Algae isn't harmful by itself but the problem it poses is that it eats the same food as your plants. So as long as you've got algae growing you've got something eating nutrients out of your reservoir that isn't part of your harvest.its just algae. u need to shade the rockwool from the light. i will try to find a pic of what people are donig.