"RE: Virkon" 7:43pm Friday 21st Sep | message edited once
joined: 13th Jul 10 last here: 11:31am Saturday 7th Sep posts: 3012 from: West Yorkshire
I always dose to this level and don't experience any problems. Since I fitted my drum I don't have to clean the filters as often if it was a weekly dose though I would dose 5-10 grams per 1000gals.