question about right coralife bulbs

[Bravofleet4]

Hi,

After reading many good things, I decided to purchase a 65 watt coralife light fixture. However, I couldn't really find one that fits 30 gallon tanks on dr.fosterandsmith. In fact, the only place that sells 30'' ones is marinedepot.com

http://www.marinedepot.com/ps_ViewItem~idproduct~ES53005~idCartRow~11637827~i sKit~0.html

Although for all I know the 24'' is acceptable. In any case, if the 30'' is the one I need does that mean I have to purchase a different kind of bulb?

http://www.marinedepot.com/ps_ViewItem~idproduct~PC5651~idCartRow~11638462~is Kit~0.html

This is the one I was looking at but its only 21'' long. I'm assuming it's made for the 24''. Is it just that they use the same bulb and there's no real difference between getting a 24'' or 30'' light fixture?

Thanks for all the help. Sorry for all the questions!

[Bk828]

http://store.seacorals.net/30co6aq65wsi.html

http://kensfish.com/coralifecompactstrips.html

[fishorama]

Looks like Kens come with 50/50 bulbs, not the best for plants.