Is it possible to have too many? I have a 50g refugium full of plants with 50 lbs of live rock and a 90g with several fish, 150 lbs of live rock, and a growing coral population. Many astrea snails & similar. Both tanks with 3 or 4 inches of substrate. There is also a ~20g sump. The lights in both the 50 & 90 are Aquatic Life. The live rock (pre-hermits) was covered with a red algae that I have never considered a bad thing in any way, but never too excited about. My g/f bought 200 hermits; red and blue leg. 100 each and pretty cheap from reefs2go. I think 99% survived although we did not get notification when they shipped and UPS left them at our front door w/o ringing the door bell. So that was surprise when we looked out mid morning. Back to topic, I will estimate that 75% of that red algae is gone after less than a week. Personally I don't care (but unsure), wife is concerned. Glad I did not order them.:bowdown: The refugium does have a lot of plants so even with pretty good flow has dead spots. I think the excess hermits in the ref are a great thing. The main tank is really the concern ... and should I even care about the red algae on the live rock?