No worries my friend - I had no clue what it was when I first read about it as well.Hey Bob-
I don't want to sound stupid, but what is H202? I understand H20, but not H202, and explain how this will help? I'm hoping that this fits into the learn something new everyday category....... I just did a web search and found out what h202 is (learned that in 7th grade, guess i just smoked them brain cells away). We have about 5 gallons of water in the cloner, how much peroxide should we add? And thanks for the help, this cloner thing is my idea because we were having very little success the rock-wool/humidity dome technique. Making these fine tune adjustments is just part of the learning curve.
TMB
Basicallly, the H202 kills anything living in the water (which is good if you use chemical fertilizers like I do), but in a cloner you most likely don't have any, so it's perfect - an added benefit is that when it decomposes, it releases an extra oxygen molecule into the water (turning into H20 + 0), and more dissolved oxygen (O2) is always a good thing.
How much to use is dependent on what grade you have and also the age of your plants - I have 35% (food grade, had to order off of the Internet), but the stuff you get in your local pharmacy (3%) can be used as well.
I use 1mL/gallon of 35% on full grown plants, but 1/2 of that is fine for clones - so, 2.5mL per your five gallon bucket.
If using 3%, I'd use ~15-20mL, and see how that does for you (should work fine).
BTW, what's your issue with rockwool? Using a heating pad? That's vitally important to get consistent cloning times.