If you buy a USED controller, you should be able to save 60-75% on it...
You can find an acjr package with a dc8 for pretty cheap.
The old school kind (with the green instead of blue LCD) seems to pop up often for under 200$ including dc8,ph and temp probes.
You could probably find it even cheaper without a ph or temp probe if you already have reliable ph and temp measuring devices in place.
Deals like this
http://www.canreef.com/vbulletin/sho...highlight=acjr
seem to come up fairly frequently.