Hi there Susan!
It sure HOT down here in the deep south, like a freakin oven! I haven't lived in these parts in over a couple of decades and I'm not acclimated yet, that'll take a couple of years I imagine. Maybe never at my age. I use H2O2 at a rate of 5-10ml (1-2 teaspoons) per gallon of water, shake, let it sit for 48 hours, and then add my nutrients and pH to 5.8 for perlite. I use a dozen or so recycled milk jugs to store the water while the H2O2 does it's magic.
I wouldn't go to much stronger in the H2O2 to H2O ratio, it reaches a point of being detrimental to roots at high concentrations. If you are using 3% (off the shelf in America) then being a little off in the ratio isn't a problem, in fact I know how much of a squirt straight out of a bottle to use after this long. If using 35% industrial H2O2, be VERY careful handling and measuring, it is literally rocket fuel!
Now I wish I had the pool that came with this house fixed up and usable, it looks like a green swamp pond right now!
Peace
Keith[/QUOTE
Want me to come down & throw a couple catfish in your "cement pond" then we can get stoned and go fishing without leaving the yard!!!