2 weeks later...
Was on vacation for a week so I had someone just feeding. Apparently at one point the ripples from the return head breached the top of the glass, so some water leaked. Fortunately it seems it was caught early enough that there were no issues with the water level going too low. I think the lid on the biocube32 saves a lot of evaporation as there was minimal evaporation loss over that week.
The scooter blenny died yesterday. It was pretty lazy for a day or two before that, but no other unusual behavior (eg no scratching, no heavy breathing), so I'm assuming the copepods didn't take enough to keep him fed despite supplementing with other foods it seemed to eat. Hopefully it wasn't something more serious that will makes its way through the other fish.
I added chaeto to the refugium, another jar of copepods, and a pincushion urchin as there is now some hair algae as well as more green algae. I'm hoping to get some corals soon, too.