Hi,
For your situation, I would get two of these....:
http://aquariacanada.com/osCommerce/...roducts_id=716
....and read these threads here on how to hook them up:
http://www.reefcentral.com/forums/sh...uto+and+topoff and
http://www.reefcentral.com/forums/sh...f&pagenumber=2
Most parts should be available around Edmonton at either Radio Shack or Active Electronics.
If you aren't comfortable with soldering/wiring things yourself, you can always purchase something like this:
http://aquariacanada.com/osCommerce/...roducts_id=516