Looking to ID Algae in Sump

[DKoKoMan]

Originally Posted by CHEAPREEF

I'm getting this same buildup in my retun pump and piping nowhere else in the tank/sump, At least it looks to be the same to me. Funny thing is I have nver carbon dosed in this tank.

That does look similar... I without a doubt didn’t have any of it until I started dosing Carbon. That’s weird that you have something similar with no carbon dosing.