I don't thin the prefilters at HD will be as good as the ones most reef places sell. At least not the ones I have see at HD. Check out the filter guys, buckeye field supply or 2 part solution for the best prices on filters.
I have an ebay RO
unit that I have added a lot too. Make sure the the DI
is vertical and not a small cartridge. It should be the same size as the prefilter housings. When I bought mine on ebay, this was not the case. Clear canisters are nice too.
units waste water. Typically at a 4:1 ratio. Use the waste water for other things but there will be waste. I have a 75gpd membrane. I don't normally make 75 gal
in a day but I would not want a 25gpd unit if I had a larger tank. I want my water to be ready in a day and not a few days. I change a minimum of 50 gal
at a time though.
*180 gal Display, 100 gal basement sump, 33 gal refugium, 3x250 MH, 2x160 VHO actinics, zoos, some softies, LPS & lots of acros and other SPS.
*100 gal prop tank plumbed into main system w/ 2x96 PC lights and 1x150 MH,