From what I've researched, it'll take a higher amount to kill pathogens that have already taken hold, but a lot less for prevention. As rykmtnman said, prevention is better than reactive measures. I'm planning to not only keep my res temps down under 70, but also plan to alternate between h2o2 and some sort of chlorine treatment on a spaced-out schedule to help keep things clean. I'll see how that goes...THANK U SO SO MUCH!
I love getting real equations and being able to double check my math with it.
Also just purchased an ORP tester and cant wait till that gets here so i can start playing around with it.
I guess to kill pythium one needs about 780mV on an ORP tester so it will be nice adding the pool shock at lower doses say 1ppm at a time and watching the mV rise and finding that sweet spot to kill algea and bacteria but not toast the plants.