Probably not a bad idea on all counts, I keep a reactor and some carbon around for just such emergencies. Carbon should help with the smell too, which isn't so bad now that all the ulva is in the trash can outside. Outside don't smell too great right now though.
Had to get water flowing again first. This stuff slowed down both return pumps and I had to pull the screens and impellers to get the flow rates back up. I'll probably have to tear my skimmer down tomorrow again too. It's aerating right now but not skimming much, the air box is clogged. I also tossed a filter sock back on the returns to catch anything circulating through the tank as best as possible overnight. I'll swap that in the morning.
God what a mistake it was to buy this stuff.
Update:
Not showing any ammonia spike, though all I have for testing is API kits. So it's not exactly fine measurement abilities but at least would show me anything dangerous.
Pumps are pumping, skimmer is skimming, carbon is carbonating(?).
I can tell there is still some crud in at least one return pump, the overflow level is inconsistent. So I'm going to have to pull the impellers again soon. I just want to capture as many remaining chunks as possible first so that I don't have to do it a third time. My dual return pump layout sure is paying off tonight.
2nd Update:
Found the offending pump, at least the one that was making noise that sounded like it was straining Was the skimmer. Cleaned that and I think we're back to normal.