I suspect the largest difference between DE filters, which I used to use quite a bit, and the cartridge filter would be time to clog and replacement cost. DE powder is pretty inexpensive to replace as it clogs, which it does quite quickly as you can imagine there are a whole lot of 1um and larger particulate matter in most tanks! They last a while on RO, but tap water is relatively particulate free and runs at water pressure which for me is almost 80 psi, not easy to do with a hobby pump in any significant quantity for filtration.