Tell me why I can't use MH/T5 lighting systems designed for hydroponics?

[whatcaneyedo]

Several of the manufacturers out there make equipment for both the hydroponics market as well as the aquarium hobby.

http://www.sunlightsupply.com/ is one example. I think Hamilton and PFO do as well.

Progressive Reef www.progressivereef.com is a shop in Victoria that sells both hydroponics and aquarium products. They have a sponsor page on this forum and might be able to better answer product specific questions that you may have.