when using h2o2 can I just use the regular household peroxide? and when suppementing how much do I use per gallon? how often?

Yes household peroxide is fine just use a 5% mixture and you are fine.

It's good practice to use it every other water change durning the Veg cycle but not as important once they are into flower. By then the root should be developed and healthy.

__________________
Peace
Zandor

If you go cheap you grow cheap. - Me

One other thing...h2o2 will destroy all micro organism, good ones and bad ones.

If you use chem nutes, all will be OK.

for Organic nutes/additives, you cannot use h2o2

Should I add any peroxide to my bubbler? I'm still in the small one that only holds about 2.5 gallons but it was pretty nasty when I cleaned it out after only 10 days.

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Gentleman - Farmer

Depends do you add micro bacteria?
If you do then NO it would kill them.
If you don't then yes you can.

__________________
Peace
Zandor

If you go cheap you grow cheap. - Me