u/cabo2424

Third angelfish I bought in the hopes it is a male.

I’ve had this fish tank for over six years now and recently in the past three months, this brown hair algae started to develop in the decorations. I took the biggest decoration out and scrubbed it out and within a couple of weeks it was infested with the algae again.
How do I get rid of it without having to add more fish, shrimp or snails?

I reduced the light to 6 hrs a day. All parameters are good. O ammonia, bellow 20 nitrates , and Ive been doing regular water changes.

Help