It is a red spotted blenny, Istiblennius chrysospilos. Really good algae eaters and lots of personality.
Are they readily available, or where you just lucky to get one?

In reactors S and M white tubes are completely not transparent - it’s white pvc.
In large reactors it’s milk acrylic tube which about 15% transparency
Do you still run the stock RSM Skimmer?
I'm having no luck with the C-Skim 1800. It doesn't skim, then for no reason overskims like a mofo, then nothing again. It's impossible to get it setup
Agreed. Its really somethingLuv ur Hammer Colony buddy, looks Great