i know the water out of the fridge is filtered, but it is not ro water, but in my opinion that would be better than tap, but no way near ro, you can get an ro unit from this site or the home depot, lowes etc. but if you have a large dt i would get 1 from this site mine i bought at the home depot and it only puts out 12-14 gal. per day i have a 150 gal. plus a 55 gal. sump/fuge so i need 20 gal. a week i wish i had got something a bit bigger as getting 20 gal. out each week is a royal pain, takes about 3-4 days to collect it all so get as big a system as you can use and still fill your coffee pot and tea pitcher and what ever else you can think of to keep the water situation at home efficient. i end up usually still buying 10 gal. a week it sucks how big is your tank, and do you have a sump/fuge tobin :happyfish