The 50/50 probably means the light is 50% actinic or pseudo-actinic and 50% white light.

The fixtures I've bought from the hardware store are designed to hang, but i've always managed to set them on the top of the tanks. It may take a little thought to make them look nice, but I think you'll be happy with how they work, and the cost is a big plus when compared to aquarium lights.

I actually set the bulbs themselves on the rim of the tank sometimes and it was fine.

Try to get a 4 bulb set up. I used a double on my 20 gallon and that was OK, but 4 would be ideal IMO for a 30 gallon. Like I said, I used a 4 bulb set up to light a 60 gallon. If you can only find a 2 bulb fixture I'd still try it because VHO or PC aquarium lights are not only expensive initially, but you'll be spending $35-$75 per bulb every 8-10 months.

I was thinking about the 40 watt bulbs and the 40 watt fixtures.

They make em and I have a double 24 inch 40 watt fixture I used on my 20 gallon.

They make 2 foot, 4 foot, and larger. I'm not sure about 3 foot though.

I measured my 24 inch and I know they're avaliable at hardware stores.

Try this T5 lighting system: http://www.drsfostersmith.com/product/p ... atid=16770

It works GREAT and the bulbs are awesome.