tom, i have a container in basement that i heat the water to 78 degrees and ariate.i allways add seachem's prime to this water. then it is pumped up to tanks upstairs and basement. every day there is a tank or two to change water 50 or more %. this regiment works great for me and keeps things consistant.thats where EI comes in so handy.livestock are so much healthier with these water changes.regards,cornhusker