This bryopsis:
is persistent, loses feathers during treatment:
by Seachem Reef Advantage Magnesium, ESV liquid magnesium, Kent Tech M, only stalks left, then returns back.
Some external layer becomes slime-like (desintegrates, maybe), but not disappears.
Same happens with some kind of short and wiry red turf algae - becomes bleached and softer, easier to tear off:
Side effects:
some corals are bleaching and declining, most - not. Die-off on the beige porites (all are Christmas tree rocks, including green pavona):
Green pavona from this shot started to bleach recently, after switching to TechM.
Green porites on the photo above - too, reddening, closing, some even dying, but in less extent, then beige porites.
Unaffected are:
Small Tridacnas, commom brown porites (Xmas tree rocks too), brown with green center porites (Xmas tree rock too

), montipora, birds nest (covered by bryopsis, but well alive), stylopora, pocillopora, scleronephthya, toadstool and cabbage leathers, baby sun, turbinaria, blasto merletti, red kelp and blue ochtodes.
Condy anemone unhappy, but alive (still worse after switching to Tech M).
What is interesting, that in a high flow bryopsis continue to grow - nice green and healthy - on the glass, while declining on porous surfaces.
Really would like the more safe and efficient treatment
