Halides keep burning up.
 

two weeks ago I decided to switch out my old 250 w de halide bulbs. After a week or so one of my new bulbs would not light. took it back and got a new one. Today same thing happened to the new bulb. Now I am wondering if it is my ballast or am I just having bad luck with bulbs? Any ideas?

tell a little more about your set up...
Type of ballasts, brand and if it's diy or manufactured unit, age of components etc...

unless you have a bad batch of bulbs, the ballast is probably having issues.
don't know how you'd measure that though.
I guess simple is to check the contacts to the bulb? and arcing? corrosion?

It's an aqua medic 48" 2 250 watt and 2 T5 and running off an aqua medic combo ballast. There are no corrosion issues but the ballast is about 6 years old.

I know I have an issue with AM in our store fixtures, but they fixed them in newer versions (mine are about 2 years old).

Ken

I'd say there is a 90% chance it's your ballast.

Maybe a good idea to buy some used, cheap or free bulbs in order to tinker around with it to define/fix the problem.