View Full Version : MH lighting ballast output

10/02/2017, 10:06 AM
I have a MH setup from the 1920s, se 250w x3. My question is it typical for 2 diffrent ballasts to output different wattage? All are 250w however with 20k bulbs I have a blue color on one ballast and the other ballast controlling 2 bulbs is more of a 14k. All bulbs are the same 20k and I have swapped bulbs to verify it's the ballast.
Any recamendations on new ballasts would be great, I need to control 3 250w MH

10/02/2017, 10:24 AM
Swapping bulbs and having the same issue confirms your thoughts.. They aren't driving the bulbs the same way..

Some choices on ballasts here..
Or you can roll your own,etc..

Which bulbs do you have?

10/02/2017, 10:59 AM
Take one bulb off the ballast in question and see if driving one bulb gives you the same color as the other ballast. My first guess would be that the two bulbs being run off of one ballast are sharing the 250w load, decreasing drive intensity on them, resulting in the color shift.

Not an electrician so not sure if this really even makes logical sense.

10/02/2017, 12:02 PM
Thanks guys the bulbs are the cheap pulsrite

10/02/2017, 10:59 PM
Are you going to stick with the pulsrite?

This is a decent electronic ballast that would be good for those bulbs. You would need 3.
https://www.marinedepot.com/CoralVue_LuXcore_Selectable_150_250_Watt_Digital_Electronic_Metal_Halide_Ballast_150_Watt_Electronic _Metal_Halide_Ballasts-CoralVue-CV25036-FILTACBAMHHFEB-vi.html

A little more expensive but from Hamilton. They are one of the only companies out there who are staying invested in metal halides for aquariums so I prefer to support these guys if I can.