I have 5 rbp's in a 125 gallon. I started with them when they were just a few weeks. When really young they were not light sensitive. Now they are light extremely sensitive and skittish. I tried a bunch of things, some of which helped. First, I painted the background flat black. This calmed them down. Second, I gave them less places to hide. Without the hiding spaces they were forced to come out. Third, I tinted the hood glass with automotive window tint to soften the light. This helped somewhat too. Recently, I bought blue LED moonlights from Doctor Foster and Smith. The P's are far more comfortable under this light than the white light.