The deal with problematic algae is that over time, detritus and nutrients settle at the base of the plant or on the rocks and nothing removes it, so there is a food source irregardless of water quality and unless you can get rid of the settled detritus on the live rock and sand you will continue to have outbreaks and returning difficulties, Ive used cucumbers and conchs for the substrait, tuxedo and long spine urchins for the live rock and walls, ive lost two abalone and one tiger cowie to the long spine, the fish have been spiked several times but have survived. as the long spines are getting bigger, i will remove them soon, so you can get a long tool and start pulling out the longer algae, the urchins will cruse the area and clean up the detritus on the rock, next time it comes back pull out the long stuff and eventually it will start to dissipate. I have been able to clear my system up apprx. 70% and am working on the remaining. This is a point where a lot of hobbyist leave the salt side, but if you are aggressive in controlling the algae, it will eventually subside if you have animals in the system that will clean the areas once the long algae has been removed. pm me if you have any questions on what i posted here. hope something here helps. I do intend to leave some algae in the system, the chromis like to spawn in the turf algae and fight me when I try to remove it.