I was looking into upgrading the lighting for a 36"L tank (stock hood is a 20W NO fluorescent) and found it very disappointing that many of the Coralife light fixtures ran 65w bulbs although 55w bulbs seem more readily available. Further reading has revealed that 65w bulbs and 55w bulbs are the same and their output is determined by the ballast. While this may open up a few options I was wondering if anyone has had any experience with this type of lighting that substantiates the assertion that 65w/55w bulbs are the same. Thanks.
55 W CF bulbs can be overdriven just like an NO bulb can. I am currently overdriving a 36W CF with a 40W ballast.
That being said, all the ballasts I have ever seen are labelled to drive 55 watt tubes, not 65 watt. In fact, when I look in my lighting catalogs for Osram, Philips and GE, I find no references for 65 W bulbs, only FT55W
My 24" Coralife Aqualight made by Energy Systems Unlimited has 65W listed under Power Output on the lable and a bulb with 65W printed on the insulator. But I dont know if the lumens output by it are any greater than the 55W I keep seeing for sale now ???
Thanks for the response guys. I especially appreciate the research concerning the catalogues. Just to add some substantiation to my original post here is (so far) some of the more compelling arguments for the bulbs being interchangable.
http://www.hellolights.com/55watblu7121.html
http://www.all-glass.com/products/lighting/lighting.html (click on the compact fluorescent photo)