whats the best lamp for an electronic ballast

Why is the sky blue?
Why is the grass green?

Probably one that was designed to work with whatever ballast you have bought?

that dont realy answer my question, if I knew what was best I would not have asked

what he's saying is what ever electronic ballast you have every light will for the same for it...example if its a 400watt ballast then a 400watt light if you want to get technical then a "high pressure sodium light"

But what type of ballast is it? Any photos of it or anything on the ballast itself?

250 w
400 w
600 w
1000 w

Also Metal Halide or HPS?

A 1000w matal halide bulb with a ballast for a 250w HPS wouldn't do a lot of good, or vice versa

Can't really help apartfrom that...