I just have some pukani in a brute with heater and PH. Phosphate is at .8 after few days. This rock has been soaked in bleach, through a muriatic acid bath then dried out before starting. I am getting ready to start tank soon so I am curing a little at a time since I cant cure it all at once. I plan to cure the bigger pieces when it warms up outside in a trough covered, but I am going to get these cured and start the sump running so I wont have a long cycle hopefully.