I said: > To generalize. Anion resins, 14kgr/cu.ft. Cation resins, 18-22 kg/cu.ft. > I think its 17.1 ppm /kg. Actual capacity depends on regenerate used > (4,6,8,or 10 lb/cu.ft) and ion mix. In line 2, it should be 17.1 g/cu.ft. To figure, divide your ppm by 17.1, that will give you grains. Divide grains by 1000 and that will give you kilograins. 400/17.1/1000 = .0234 kg At 10 gpm = .234 kg/min or 14.04 kg/hr Need to know the ration of anions to cations now. Assume 50/50 Now 7 kg/hr cation, and 7 kg/hr anion. Assume resin capacity of 14 kg/cu ft anion and 21 kg/cu. ft cation. Require 1/3 cu.ft cation resin per hr Require 1/2 cu. ft anion resin per hr. Double it to be safe and calculate for one regen each 12 hrs. Best Regards, Bob Mesick Remco Engineering Water and Wastewater Treatment Systems http://www.remco.com [log in to unmask] ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################