Updates: so itās been about a month, and the blue algea hasnāt come back since I treated it!
I dosed all my tanks that were showing signs and not a single one has an outbreak anymore~
Only one fish has died since: my albino pleco. But Iām not sure why, she suddenly stopped eating and I tried putting a variety of chopped veggies in and nothing. She just slowly got paler and paler over the course of a couple weeks. Iām really not sure what happened though. All of my other bottom dwellers/shrimp are okay so even though itās not impossible, I think itās unlikely that she managed to eat an undissolved particle.