L/f: T5ho 4x24" reflectors

[jepree]

I have an AQUAMEDIC T5HO 4X24" lighting assembly and was wondering if anybody has or knows of where to get individual or complete reflector assemblies??? And how much of a difference can i really expect from them? The current reflectors are the whole back base of the lighting strips but i was told individual reflectors can make a substantial difference and so I'm on the hunt with no luck as of yet!