Brown Algae ID

[petrea92]

Over the last few weeks, I have seen a new algae outbreak and I’ve been unable to properly ID it. It seems to be encrusting and does not come off with a tooth brush. My CuC doesn’t eat it.

My LFS suggested a pinchushion urchin, but I’m wondering if there’s an alternative. I don’t want the urchin to eat coralline algae.. I’d rather get to the root issue.

Can anyone ID this algae? I don’t think it’s the typical algaes (Cyano, Diatoms, or Dinos) and, as you can see, it doesn’t touch the sand.

 

[EeyoreIsMySpiritAnimal]

How old is your tank?
Is the algae fuzzy or completely hard like coralline?

If it can't be removed with a toothbrush, it may be more of a stage in the maturation of the rock than an outbreak.

If it's not affecting your coral, I'd leave it be for now.

 

[petrea92]

How old is your tank?
Is the algae fuzzy or completely hard like coralline?

If it can't be removed with a toothbrush, it may be more of a stage in the maturation of the rock than an outbreak.

If it's not affecting your coral, I'd leave it be for now.

It’s a combination, I think. It’s the tougher, dark brown encrusting algae, which then has a softer brown hair algae growing in some areas that can be brushed off in some of those areas.

My tank is almost 3 months old, and I did go through some diatoms, but this stuff is tough and much different.

My phosphates are just about 0, so I’m also concerned that I’m over filtering. I’m trying to find a stable, healthy balance, but I am currently doing 40-50 % water changes/ week. Parameters have been stable. Salinity stays at 1.25 and temp stays at 78° but sometimes reaches 80-81° with the heat during the day.

All corals seem to be unaffected, aside from my GSP that 90% opens and seems healthy. The other 10% only recently quit opening the last few days, and I’m not sure if it’s related to the algae.