GHA Bryopsis? Something Else? ID Help

pdogg77 · 2026-10-20T15:24:57-0400

Hoping for some help here. I'm trying to figure out if I'm dealing with GHA, Bryopsis, both, something else?

This is this tank: https://www.reef2reef.com/threads/pauls-90g-cube.362773/#post-14570452

To sum up it is 10 years old, started with TBS live rock and sand. Went through a period of heavy neglect. This is what is left after a lot of manual removal, cleaning up, etc. and I can't seem to get it to go away or really make a dent in it. Any help would be greatly appreciated.

Thank You!

officialreefbros · 2026-10-20T15:27:43-0400

Picture? Bryopsis looks like it has branches!

Baldyreef · 2026-10-20T15:31:28-0400

im leaning more towards gha than byropsis
#reefsquad

EnterName · 2026-10-20T15:33:04-0400

The microscopy images look more like Derbesia or similar hair algae, not Bryopsis. Bryopsis has symmetric branches that are quite dense and well visible under the microscope.

pdogg77 · 2026-10-20T15:38:44-0400

EnterName said:
The microscopy images look more like Derbesia or similar hair algae, not Bryopsis. Bryopsis has symmetric branches that are quite dense and well visible under the microscope.

Thank you. As I suspected. I'll continue the GHA battle :)

officialreefbros · 2026-10-20T17:03:15-0400

Agree woth the GHA. Make sure to test frequently! Looks like a big outbreak and I've had that eat all the nutrients and cause dinos to jump in too

pdogg77 · 2026-10-20T17:19:02-0400

officialreefbros said:
Agree woth the GHA. Make sure to test frequently! Looks like a big outbreak and I've had that eat all the nutrients and cause dinos to jump in too

Yes it is / was a decent sized outbreak. I'd say it is "getting under control" now but there are just some tough spots. Mostly where I had coral die off and bare skeletons. It is very clear where there are rough, porous surfaces with little to no other life on them. It digs in there.