Heisenberg makes a great Tea. I sort of just ran with his ideas, and borrowed some from VermiT as well (the co-owner always comes into our dispensary) and my plants fucking LOVE it.
I use Tea because my res is always between 65-72, so I'm really safe using it, but I don't know at higher temps. The friend I am constantly referencing just chopped down 6 SFV OG's out of a recirculating DWC system in a 4x4 tent. a few weeks ago, if even that, he had his Blue Dream disaster in the filing cabinet with all the mold, bud rot, and root rot.
Anyways, his reservoir temps seem to be about the same in both the cab and the tent, but these SFV's were all champs, with NO ROOT DISEASE and they were in the same hot water as the Blue Dream, the difference was that it was a recirculating system, constantly churning in new oxygen, just like your system does. He also had 45-55 gallons of water in the system, so that helped a lot too. But he was using the Heisenberg Tea, and not only did his plants love it, but they had VERY healthy white roots, with no mold or disease the entire grow, even with a cab sharing ventilation with his tent, that was loaded with mold spores!!
I know that information was kind of confusing with me saying "No tea, yes tea" but it is only because I'm still figuring it out myself. I just started reading this months issue of Urban Garden, it is all about organic gardening and brewing teas. So I'm still learning. But so far it seems like an excellent idea to keep your reservoir fresh, but at the same time it has the ability to go completely south. It all seems easy enough to understand, just read up on it. Search for "Heisenberg Tea" here on RIU, that is a great source! I also am talking to the VermiT guys, as well as referencing my Urban Garden magazine. I'm about to actually borrow my friend's Organic Chemistry book, so I can get a better science-based understanding of all this.
H2O2 will keep things sterile, some people swear by it.... But I'm having a lot of fun brewing my own tea, and I'm saving money. I have so much tea after a brew my outdoor plants look amazing as well. Now my neighbors don't wonder why some of the plants in my yard look like crap while I'm always unloading soil and fertilizer out of my truck.
Right now they just think I'm farming annual's to sell the local nursery, and I do a good job of having Morning Glories always growing in pots around the house. No I don't get high off of them... I know a chemist for that reason.