Hi
Unless you need super pure or large amounts of water .Your best bet is a rainwater collection system.
I keep a 180 gallon system for both my plants and aquariums. Works great and costs nothing to operate.
gary

That's true, if you have the space for it. Unfortunately, I live in an apartment, and collecting and storing rainwater will be nearly impossible.

I considered simply using a drinking water filter like a Brita, but the difference in price between one of the cheaper RO systems and a good water filter is small enough that I figured I'd check out the quality of the smaller systems.

The one in your link is going to have to be changed according to the amount of dissolved metals and sludge thats in your cities drinking water, here in Philly we have very high metals and minerals (and other crap they wont admit to) that leads to changing cartriges at least once every two to three months, sometimes monthly! so I use mostly rain water, but I do buy spring water that has been filtered through a RO filter, I wish I could afford a nice RO sysytem but cant right at the moment =( I use the sring water for plants and drinking, but the crap thats in the water can and does get absorbed while bathing too =(

Hi
I'd guess in an apartment you wouldn't want to install an expensive system anyway.
You might check out reefcentral.com. They have an in depth FAQ section on how to choose a system. On the left side of the main page.
gary