Um ...... from what I was able to read about those solar system ballasts, they use some kind of proprietary bulb. It's not just any random 175W halide with a medium base. Nobody but Coralife has a product that dims halides -- this concerns me. (Icecap
kind of does, but only a half-intensity output -- not a ramping dimming like these.) It's your risk of course, but, I urge caution before committing to anything. You could be risking exploding bulbs -- I've had a halide bulb explode in my tank and it cost me several pieces of livestock due to the UV burn
So please be absolutely, absolutely sure you know what you're doing!!! Check that the bulb you want to get can work on the ballast -- maybe send an email to Coralife and ask them.
Good luck!