So I have this rock that was completely covered in gha. It was the diamond gobies home base. My hippo tang cannot control the algae quick enough and it was upsetting a zoa colony. So I pulled the rock out and dumped a whole bottle of peroxide on the gha till it bubbled. I then left it soaking for 30mins might have killed the rock of all bacteria but I think I got the gha will see in a couple of days. I'm about to home my diamond goby as well he likes to spit sand on my 15 acans. He is a smart fish he'll do it in front of me till I look at him hard. Then he will sift sand a couple of times in place like I'm not doing anything.