garlic is also known as the russian antibiotic
but since its not a manufactured drug,dont expect them to work really fast and also you need wholistic approach,like more than usual water changes and kung puwede thrown in some UV therapy,hehehe
i agree maybe we wont totally eradicate the vermin in the tank but keep it under control from anymore outbreaks,lalo na since from time to time we introduce new inhabitants sa tank at least we try to make it an unfriendly environment for them to thrive
nowadays i rinse the NSW plastic water tanks and even the pumps with fresh water sakali mag corssinfection amongst the tanks as i use the same tanks also for draining dirty waters during regular water maintenance