Me again asking more questions(annoying newbie ), I'm sure you must tire of silly questions like this but I want to make sure I do this right and more importantly don't blow myself or my light unit up(the light being more important ) I have a Dymax 4ft light unit, I can't find the exact one that I have and the only websites with pics I've managed to track down are these; http://www.mydymax.com/index.php?page=s ... t&Itemid=1 http://www.adec.com.sg/products/lightin ... ht/ob.html The second is probably the closest one to my lighting that I can find, this is my light unit; Please exscuse the tape on the filter tubes, that's my paranoia that they will get knocked out of the tank so I have them sellotaped to the back As you can see from the pics one of the tubes is 28w blue the other is 12,000k 28W, obviously these are not ideal and they need changing, the plants seem to be doing fine with the lighting but I do want to change the light to something more suited to plants when I move the unit over to one of my 4ft tanks. I've been looking at lampspecs and the posts regarding the tubes from them and I like the look of the osram 880, but which if any are suited to my light unit? Am I correct in assuming that all T5 lights have the same diameter / connectors or do they vary? I don't want to buy a tube and it doesn't fit. Only other info I could get off the light unit is a small sticker that states; Dymax OB 392 Volt 220V - 240V 50HZ Power 56W (2 x 28W) Hopefully that is enough info for you guys to help me Thanks. Kel.