Sorry DAWG not to thread jack, just in response to the comment you made to daveroller. I would say H202 is both good and bad, like mostly everything else in this world. If you are using just standard peroxide like you would use on a scrap you'll be fine if you don't over do it, I think I was using like 15mL or /gal to take care of pythium. The reason people will say it's bad because in excess it is just that and that's the fixation. peroxide introduces oxygen radicals, oxygen radicals are extremely reactive and actively oxidize things. That to some extent is good at the root zone but bad to the tissue that really has no use for oxygen. It's a balancing act as well. Though as regards to the beneficial microbes depends on the system no, it will not kill them all. Got to remember you are talking to a lot of people with no true microbiology experience or background. Some yes. Most? Not at all. At lot could tell you that then if you asked them what a catalase positive organism is they would be clueless. If you are unaware, no judging if you are, catalase is the enzyme some microbes possess to break down hydrogen peroxide into water and oxygen. Doesn't kill it at all. Example, if you have some decent finger nails go pour a little hydrogen peroxide in the palm of you hand then submerge the fingernail tips of your other hand. Most likely if you look closely you will see some slight bubbles raising up from under your nail. That is catalase positive organisms breaking it down.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1855589/
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC239483/pdf/aem00167-0117.pdf
And while not MJ. Mycorrhiza has been shown to have an impact on taking care of oxygen radicals like those of H202. Just as an example. So just take it for food for thought. Like I said it can be both good and bad depending how, when, and/or why it's used.
http://www.agriculturejournals.cz/publicFiles/11529.pdf