fixture doesnt work time to retro fit

this fixture is designed to light up warehouses and other LARGE open spaces. Not at all designed to light up a little (comparatively speaking) box of water. YOu could try it I suppose but I somehow doubt the end result would be much like the output of the aquarium-designed fixture but at a third the price. Actually more like 2/3 the price once you figure in the price of bulbs. I'm as stingy as they come but imho nearly $200 is a lot to spend on an experiment.

of course I suppose if it doesn't work for the aquarium you could sell it to somebody for a big garage light or somesuch and get your money back that way.

Whats wrong with your current fixture.
Maybe you could just fix it... or send it to me...

There are only two parts. Ballast and lamps.
Can you test the lamps in someones fixture?
New ballasts, that could be used in another project, or sold, if not needed - will cost less than the high bay retro fit.
The high bay retro fits usually have one or two reflectors, by the way. That ad suggests only one. It fits fine in the unit it ships with. Retrofitting it into an existing fixture might be a frustrating cut and rivet project.