ID on Algae? I don’t even know...

[saltysailor]

Tank finished cycling. Have barely had anything in it. There is almost a red streak going across the rock. Seems to be coming from the flow of the return pump because that was the way the head was facing? I have no idea.

 

[BlennyTime]

It’s possible the flow of the water kept algae from growing where it was blowing on directly. It’s sort of hard to tell from the pic though.