Thanks, DVNO!
Still fighting heat issues in the display. Ran most of the evening with only one light, the canopy doors open, and a Vornado blowing on the tank. Maybe the algae will die. I've set up a meeting with the company that came up with the exhaust fan idea to find something that moves more air.
In the meantime, the dottys seem to still be playing the spawning game, but I've seen no egg masses yet.
Downstairs, there a load of spawning going on. I've counted 49 of these egg packets, possibly from RSF (formally DIBS) nassarius.
And a new egg mass tonight, maybe cerith:
Along with a whole bunch of ciliates(?):
That last photo at around 200%:
As you can see, the eggs have started dividing, but haven't hit blastula (roughly 128 cells) stage yet.