I have both Korallin 1502's the denitrator and the calcium reactor, they have both been running for about a month give or take, the denitrator has brought my nitrates down from 100ppm to 0, now the calcium reactor I'm still fiddling with, my effluent is 6.5 and only putting out 380 and the calcium in my tank is 370 so we'll see, so far the equipment rocks. I have a 5 lb. bottle I'll see how long it lasts.