I've been fighting this for months now, I think the outbreak started due to my LFS's R/O water started to decline (went up to around 100ppm!) and since then I've been invaded by this green stuff. I think it's GHA but it looks paler to me and is easy to pull away. I put a sea hare in 2 weeks ago which isn't touching it which is another reason that makes me wonder is this GHA or another type of algae needing different methods of removal. I'm tempted to try API algae fix but that will be a complete last resort. Advice is appreciated.
Pete.
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