my opinion/rationale>
Green hair algae (the generalized term) is universally distributed in aquatic and marine systems via ubiquitous airborne spores along with cyano red and green, and several other forms of undesirables like micro algae...constant bombardment into our tanks via the air.
they can and will repopulate based on variables in each tank unless the owner can find that elusive sweet spot where corals grow and algae/pest does not, long term. I personally have never found the spot, its something to strive for. I see it posted from time to time. first I need to see a 3+ year old tank or more to believe anyone has found any sweet spot, but provided thats in place Im really looking for what works long term and its 2% of tanks online who find such a long term sweet spot where they magically get no pest algae growth of any kind for years. Agu is that man it still frustrates me / sheer jealousy ->
98% have algae to deal with so your regrowth Simon is common, but you might agree its much controlled compared to the first run
That spot I treated and posted pics of in the first pages, there is one tiny strand of gha real low to the rock about an inch over that came back this week, in about a month it will be a pinhead sized patch like the one I burned, that's my regrowth, will have to apply 1 drop of peroxide again about Feb 20th. Im not worried at all, this is the common cycle, we didn't think peroxide would stop algae it was just known to instantly kill it so that I get to never test for phosphate again for the life of my tank.
phosphate targeting is not long established in reef circles
it is a post 2004 webwide bandwagon (nitrate before that) and while helpful it does not cure pest invasion it merely selects against it. you can still follow water maintenance trends of maintaining incredibly low N and P and get invader X -> thats a letdown to me, so a major tenet in this thread is that water maintenance is indeed not the secret to an algae free tank and neither is a clean up crew. We followed methods that didn't repeatably work, there was a missing variable, and thats effective manual removal as the primary action.
water maintenance determines how often you prune and thats it. keep water within the ranges coral needs to grow, then don't worry about it, thats my way.
peroxide buys us time to keep tinkering with better starvation methods while still trying to keep the corals fed.
its mainly a reset button as we begin to see more and more that clean up crews have been overhyped to us for a long time.
notice no crabs are coming along helpfully pruning this stuff until you burn it first
bryopsis and other inclusive genera that look similar, macro algae like dictyota, neomeris etc along with red brush algae like gelidium and countless other rhodophyta members, members of the diatom families, are not airborne they are obligate hitchikers
even though you've treated peroxide in certain areas of bryopsis growth, there is no telling what mass lies deep in the rock or up inside niche areas that peroxide didn't get to so these popups are simply hiders revealing their places.
