I generally add about 5mL (1 tsp) of H2O2 per gallon of water in my systems weekly. But I have been known to use twice that, or even 3 times that at the first sign there is something in the system. Though I don't usually use it with seedlings. I usually wait tell their a few inches tall before adding the H2O2 because seedlings roots are more delicate. But If I do use H2O2 with seedlings, I cut the dose to about 5mL (1 tsp) for "two" gallons. Though because it dissipates so quickly, I would re-add it every other day. Or at least every 3 days. And if I am trying to get rid of a problem with established plants, I'll re-add the H2O2 every couple of days instead of weekly.
|