Here is mine again,...I posted it on page 6 originally,...supper easy,...all gravity, but you kind of need to have this in your basement. My systems total volume is 1000gal, so when I do a 10% water change I take two 55gal barrels off line(#1 & 2). You can also run the same set up with 2 barrels or more depending on the volume of your system and % of water you want to change at a time. My RO-DI takes 24hr to refill the two 55gal barrels, with the rest of your system continuing to run except for the 30 seconds it takes me to turn the three valves off.
Happy Reefing ! ;)
Post on page 6 > Well here's mine...very simple...my system runs through 4 barrels continuous. For water changes I drain barrels 1 & 2 with the valves at their bottoms,...also I shut the DT return valve over barrel 1 off and open the valve over barrel 3 temporary redirecting the flow to barrel 3 and shut the valve between 2 & 3 so I don't get any back flow into 2. I then do a squirt out with my hose of any bottom settlement. Now ready to refill 1 & 2 .My RODI unit fills barrel 1 from a flote switch at the top...when its 1/2 filled I dump the first 50gal bag of IO. I have a batch type mixer with a ss shaft and prop that I switch on...when its almost filled I add a second bag of salt. Barrel 1 dumps into barrel 2,...when they are both filled and temp reaches DT temp...Done...return a couple valves and all 4 barrels are back on line. The hardest part is dumping the salt. :)