Metal Halide - Choices

[Myka]

Originally Posted by plutoniumJoe

What I am reading in the article though states that you get more light for less power out of two 400 vs 3 @ 250.

Keeping in mind I didn't even glance at the article, what I think they mean is that you get more intensity out of the 400w bulbs than you do out of the 250w bulbs. You use 50 watts more using 2x400w than 3x250w, but the intensity you get out of the 400w bulbs makes up for that. So essentially if you get more intensity for close to the same amount of electricity, the efficiency is greater using the 400w bulbs.

Having said that, I still think you're better off keeping 3x250w over a 6' tank unless you get some sort of custom reflector for 2x400w that spreads the light over the 6' length, but doesn't spread it past the width of the tank. Now that would be interesting...

[lastlight]

Sorry I wasn't thinking specific ballast data you used generic numbers so I thought I was missing something. My radium is a 250w and burns at around 333w so I fully get that. I always thought the e-ballast would use a little less. For example my same Radium on icecap uses 244W. Not sure if this was the old or newer icecap but I didn't think any e-ballasts overdrove bulbs.