i got a question about lighting

[mr funktastic]

ok i plan on adding quite a few more plants to me 20 gallon tank. now i have read that most kits come with crappy lighting but i was checking out my flouresent ballast and it is rated for a 50 watt bulb. now i have never seen an 18" 50 watt bulb. i havent looked that hard to be honest but that is such a huge difference between what i have in there now. i have a 15 watt coralife bulb in there now and it gives off a lot of light. where can i get my hands on a 30-50 watt bulb? can i buy it at a normal store like home depot or sumthing? hope u guys can help

 

[malkore]

You can't.
It sounds like you may have an electronic ballast instead of a cheap magnetic one. Electronic ballasts are often 'load sensing' and detect what bulb it's plugged into, and delivers the right amount of wattage to it.

Any 18" normal fluorescent will always be 15watts, unless you overdrive it. Your ballast may be good for that, but you'll need to determine the exact brand/model number of the ballast so you can search online to see if its usable for overdriving. Then you could do a 3x overdrive and run a 15watt tube at 45watts.

However, the only point in this is to cheaply increase lighting so you can keep aquatic plants.

 

[aqh88]

There are 4 types of fluorescent lighting. Normal output(NO), high output(HO), very high output(VHO), and power compact(pc). In all of these the length of the bulb determines the watts. So an 18" NO bulb is 15w. A 48" NO bulb is 40w. The HO and VHO use different phosphours to produce more lumens(visible light) but whether your ballast would work with these lights I don't know. VHO bulbs are also fairly expensive. PC bulbs are bent fluorescent bulbs so they have more length in much less space. The fixture and bulb cost is similar to VHO but the PC bulbs tend to last longer and work a little better but you'd have to retrofit your light to run PC. For HO and VHO you'd have to check the abilities of your ballast and look online for the bulbs. I doubt you'll find them in a hardware store since they are usually more costly and not as practical or necessary for shoplight and home light uses.