I'm still looking for a pair to put in my 40 tall, and was thinking maybe a pair of these guys?? I know they are very sensitive and that they can be a hit or miss but I'm curious on your guy's input. As it says I have a high pH, it is very stable tho, never moves. And my tank is very stable and has been cycled for about 8 months. I'm curious, will these guys work in my tank, I don't have experience with them. ??? Also I have an adult angel, 5 harliquin rasbora (going to be 10) and a BN pleco in this tank. Thanks guys!!