The CUC looks good, I'd keep an eye on the red legged crab, I've read they are a little more aggressive. Do you know if it's a red legged or a Scarlet Reef Hermit?
I like your light design, the only fear I would have, would be water getting in contact with the bulb, will you have some sort of clear cover for the bulb? Do you have a pic with it mounted to the refugium? (I'd like to see how it all goes together
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