Handy fact about manual removal
Putting liquid X (peroxide, Kent, brightwell, Kalk pastes etc) on bryopsis outside of tank isn't true manual removal, that method still skips a work step and skipping work steps is what sustains an invasion. It will typically beat water treatments however, and it takes a back seat to the real method of manual removal (rasp method)
We can now attain a 100%, non variable bryopsis cure using the rasping method which was invented in the peroxide threads.
It is a known cure, all the time, because without holdfasts bryopsis will not thrive past simple export. Anyone feel like testing... make a test rock it takes all of ten minutes, anyone here just post up your worst bry.
the reason bryopsis regrows after external treatments is due to its anchoring characteristics. Cyano is opposite for example, or dinos.
When we do any action that kills or mows only top end plant mass, and some has safely infiltrated the surface area of rocks or substrate as holdfasts, that housed mass simply grows back. This is why 2000 level mag works most of the time but had variance. Its why grazers that are not parrotfish or hawksbill turtles have variance on bryopsis patches.
*1800-2000 runs routinely kill all the mass, but for the times we can see it didn't, holdfasts were at work and porosity/other variables changing among tanks.
The rasping method is the bunker buster for anchors and if a test rock yields regrowth, then rasping wasn't done correctly. It's a digging move, not brushing, brushes aren't metal. a parrotfish bites rock and poops sand...much meaner on an algae target vs how a nudi removes bryopsis. That's rasping vs manual removal.
By actually going as deep as needed with a metal tool to remove all physical mass, not any plant remains even if you don't use a chemical...so the test rock is forced back to zero plant mass in one setting.
any of the above chems are then used on the worked areas as bit cleanup.
(But I don't want to rasp, it will look bad)
See rasping threads, no it doesn't. The bryopsis is what looks bad, a cured tank spotted back over with coralline since plant dominance was stopped looks great. That's like saying we don't want a free car paint job since the primer stage will have a gray look. If we took care of the original paint job, a redo wouldn't be needed.
The method is more common in nano reefs for obvious work differences, but, large tanks can also use it too--simply act while the bryopsis is on a single rock, don't wait 18 mos in hesitation. Roughly 75% of bryopsis challenge tanks will do fine with water dosing only of magnesium. We like to deal with the outliers that cause people to just about start over.