I recently built a saltwater mixing system that has literally taken all the hassle and mess out of mater changes and top-offs. I'm pretty excited about it so I thought I'd share. Maybe some folks already have something similar. Here is a picture/diagram of how the system is set up (I didn't take any pics of the actual setup so I made a sketch-up model). It's rather inexpensive, and very efficient.

It's just a simple setup with one pump and a bunch of ball valves. You just open and close the right valves for what you want to do. You can add R/O water to mix into the saltwater, mix saltwater into itself, or hook up a hose and pump either R/O or saltwater to another container, or your tank/sump. On my system I also dropped in an ATO pump into the R/O reservoir. Notice the union joints around the pump for easy, clean pump removal and maintenance. I just use an inexpensive Quiet One pump and a couple of 20G Rubbermaid Brute cans.
Edited by Deluxe247 - July 05 2010 at 12:19am