Looking for recommendations for a new light fixture

I've had my Coralife Aqualight fixture for about two years now, and I'm
disappointed to find that the electrical caps (? the sockets that
connect to the lamps) seem to be corroding, to the point where I can't
replace the bulbs without cracking the caps and exposing the lamp pins.
This is pretty disappointing. What is the average expected lifetime
of a light fixture over a reef tank, anyway? It sits directly on top
of the tank so I suppose it gets more exposure to corrosive elements,
even with the acrylic shield.

The Aqualight is relatively inexpensive, but it still seems to me like
I should get more than a couple of years out of it. I'm not good with
electrical wiring etc. so I'm pretty leery about the idea of repairing
it. Anyone have a recommendation for a replacement fixture? I'm
looking for a 48" PC fixture, preferably holding four 55w/65w lamps.
Ideally the electrical cords would come out of the back, not out of the
side as they do with the Aqualight.

Thanks in advance.