What size of tank is this going on?

I would get a nice 14-20K bulb and not worry about actinics. Even though it is overkill for what you want to keep right now, it will allow you to change your mind and not have to worry about swapping your lights in the future. Look at the 150W HQI's as well as the 175W SE setups. With just the singe bulb, you'll only need to spend <$75 on bulb replacement a year.

As far as heat goes, we are talking 1x175W bulb, I dont think the heat will be that intense that he will need a chiller, unless the tank is like 20 gal, but I doubt it is since it has a center brace. I ran a 400W over a 44gal corner tank with a single fan in the canopy and didnt have heat issues, just alot of evap. and our electric bill hardly changed at all, or at least not enough to care about.

Just my thoughts
cs