I fought cyno ... Refused to use chemiclean the LFS subscribed.
Took a few weeks though. Basted rocks daily, did 5% water change daily, hung an aqua clear on the tank and rinsed the sponge daily.
Stopped daily feedings and fed every second day, sparingly.
I also stopped all those zeo additives, went back to the basics...keeping it simple which includes no pellets or quick fixes.
I use carbon passively that's all.
