agreed but technically that wasn't the mod. you didn't hand remove it initially, you chemically suppressed it for it to bounce back. my guaranteed fix is work heavy, you have to siphon it out. and now it w be a few times, not just once, due to catchup while you do these peroxide treatments.
This system works amazing I promise. Chemiclean doesn't clear up tanks all time time, simple suppression vs real removal was the likely confound there. hand siphoning is not suppression its true biomass removal, then your dilutions and treatments are amplified not because you added more, but because you made smaller the target mass.
using chemicals vs hand siphoning is the problem so far. all tank invasions should be met with hand removal first, then any fix afterwards. the reason we don't do that as a hobby is because all the old methods don't state that as an option. we get that option from the large peroxide correction threads, working gold here and there.