ro water= no more diatoms on the sand ?

[Gujustud]

I've got the tap water purifier, and so far its been working great. I've been using it since Jan '04 and so far, I haven't had to change the filter (however it is almost about 3/4 black now, so a change is needed pretty soon).

I'm contemplating wether to buy another filter for $30, or just to buy that RODI from aquasafe. I think we should try and get those guys to allow a local pickup however. Lame when they are only about 20 mins away.