by koiservice » Wed Jul 06, 2011 7:09 pm
Costia for sure.
I personally have given up using PP for costia. If your organic load is off, you will need to repeat the treatment multiple times, back-to-back, in order to get the 5-6 hours active treatment time that's required to kill the little beasts. I only ever use formalin/malachite for costia now. One dose, UV/ozone/zeolite/nitrate-hash/active carbon etc etc out the pond before dosing. Wait 24 hours then refresh a good 10-20%.
Infact, i've pretty much given up using PP for anything these days. Only very heavy infestations of trichodina would I consider it, and even then after battering the fish with PP, the trich is back within a week or two.
It's horrible stuff, it's not as effective as it once was and in the wrong hands, it can be deadly. Even when you do everything 100% perfect, the odd fish can react bad to the D.O drop, even at low doses.