Same thing here , I had GHA but Dino’s where even growing on it! You got this tho don’t give up! It got worse before it got better for me but eventually they just seemingly disappeared or died out , I ran only blue lights at 20% for a week to not tick off anemones too much lolThe strange thing, I also have gha growing same time. It’s a mess. I have chaeto growing in a pax bellum, and have tried the blackout. I have not tried dosing bacteria yet. Since it does move to the water column at night I can see how the UV would be a good choice. I just need to order a better one and get it plumbed even if temporarily to start.