Teach me about Fluorescent Ballasts
Hey guys. I'm building a canopy for my little 12 gallon today, and it got me thinking about eventually buying some fluorescent lighting to put in there. Right now I'm just going to cannibalize two aquarium lights and make them fit. Anyway, I want to learn about ballasts. From what I can see, they generally drive bulbs that have part numbers like this... F40T12. Anyway, the "T12" part is obvious, that's the type of bulb. For a T5, it's be T5 at the end. I think the F stands for fluorescent, but what's the 40? These bulbs are 4 feet long, but I don't think the 4 feet has anything to do with the "4" in "40".
In case you were wondering, I happen to have a couple of these ballasts, as we have fluorescent lighting in our garage and basement, and we had extra lights.
My main question is, why do ballasts have to drive certain bulbs? What makes a 4 foot bulb different from a 2 foot one? I'm assuming it'd have to do with the power needed to drive it, but what if you found a 2 foot bulb that took as much power to drive as a 4 foot bulb? Could you use the same ballast? (Assuming it needed the same amperage and was the same wattage) Still, I mean I wouldn't think that fluorescent lighting needed such specific power requirements, the chemistry geek in me knows how they work on a quantum level, and I'd guess that a little more power would simply change the spectrum of light that came out of the bulb. I don't know, that's why I'm asking!