i agree..unless your well aware of how to use and it ..and for what..one shouldnt. i have tons also..but i dont recommend it to be used unless for specific things.
pp gets rid of organics. if using on fish..you need to know the right colour strength..and you need to have hydrogen peroxide on hand.
you can order from your pharmacist and pickup the next day. about 8.00 for a bottle .pp is used for getting rid of bacteria etc..slime coat problems..etc.i use it between shipments to be sure no bacteria is in the tanks .
heres an article on pp.
http://www.discusnews.com/article/cat-02/pp.shtml written by the late jim quarles..