peppermints are very unpredictable and do as they please. I have 8 of them. some of them come around in the front of the tank at daytime and there were some smaller ones I had that I maybe saw 1 or 2 times in about a 2 month period (even at night) once they got a little bigger and comfortable with the tank they came out more, but still I don't see all of them all 2 often. strangely I do have a couple that are attention hogs and come out all the time and clean my hand if placed close to them. as far as the pom pom, I wouldn't count on seeing it all too often. I had one in my 36 that I saw maybe weekly or bi weekly for a few minutes and now that its in my 180 I haven't once seen it except for the initial introduction. sadly he only had one "pom pom" when I got him and apparently that one didn't stay healthy so he has no more. but they are such beautiful crabs that I view it as totally worth the purchase when you can find them. they seem to be scarce availability so I will always swoop them up when I can because the moments I do see them are worth it.
by the way.... the tanks lookin good!