I did it! OVERDRIVE!

[dccruibay5]

Well I did it, I put the light on my 55 in OVERDRIVE! I bought a new electronic ballast for a 4 bulb light, and wired it to just 2 lights adding 50% more power to my bulbs! So I went from 64 watts to 96 watts and a little more then 1 WPG to almost 2 WPG! It was very easy for me (I was an Auto Tech for 10 years) If you are not comfortable working with electricity, DO NOT TRY THIS! This can kill you if done wrong! I am not an electrician. nor do I play one on TV. I did not sleep at a Holiday Inn Express last night, I just was careful!
The ballast has 2 red, 2 blue and 2 yellow wires along with a black and a white wire. The black and white go exactly were they old ones where. Then I took the 2 blue and attached them to one holder of one bulb, same with the red (same side if the fixture, other holder), then one yellow went to one holder and the other yellow went to the other holder on the other side of the fixture. Then I used a jumper wire to go from one pole on the holder to the other. I also replaced the holders because 2 of them looked corroded. The whole project cost me less then $30. I am sure you can find the ballast ($19.99 and HD) cheaper online if you tried. Here is a diagram since my directions suck! It is from this site Overdriving Fluorescent Lights

[Northernguy]

Have you burned any tubes out yet?
I would think that it would be hard on the bulbs shortening their lifespan.

[dbosman]

Over driving T8 fluorescent lamps doesn't burn things up quickly.
Given the relatively low price of lamps/tubes/bulbs the cost is worth it for some people. You do get more light in the same fixture.

[friz]

Over driving T8 fluorescent lamps doesn't burn things up quickly.
Given the relatively low price of lamps/tubes/bulbs the cost is worth it for some people. You do get more light in the same fixture.

Does it change the color temp?

[korith]

I have a light fixture over my 33g long that is overdriven. The person I bought it from got the ballast on clearance somewhere. Does put out a fair bit more light, no complaints. Haven't really noticed bulbs going out any sooner than before.

[dbosman]

Does it change the color temp?

No. The color and color temp, depend on the gas mixture used in the lamp.

Many years ago it would take almost 200 different ballasts to serve the needs of fluorescent lamp users. About a dozen electronic ballasts now fill all those niches. An electronic ballast senses the load placed on it and either uses a logic table or a feed back circuit to adjust the voltage and current based on the filaments.
Over driving just tricks the electronic ballast into seeing a different resistance and sending more current to the the lamp so it burns hotter. That increases the efficiency of the lamp so you get more light, but it shortens the life of the lamp as the atoms that get ionized, plate onto the glass at the ends faster. The numbers vary, but you drive a 32 watt T8 lamp/bulb/tube at somewhere in the 48 to 60+ watt range.

The main reason to over drive a lamp, is getting more light in the same space over your plants or tank. This came about before T5HO got to be as readily available as it is now, and the price came down enough to make over driving less desirable. Over driving is a DIY project and DIY electrical projects scares some folks.