When should ballasts be changed?

I'm needing some info on my ballast..
What I'm looking into is:
How long will my ballast last and when should it be changed...
I'm running 1 250 watt aqua medic single unit...it's being used 8 hours always nothing more or less..
can anyone Imply?

 

Until it stops working or working right.. Its more about changing the bulb than the ballast.

 

we'll not eaxctley as other forum members have descirbed it...
thier was talk on other forums that be aware of keeping good quality lighting in your reef...this is done by changing your bulb on also your ballast...so making sure you keeping a close eye on your ballast when it's about to burn outor give way...

 

IMO, ballasts should be changed if they don't work, or if you change your bulb type, and it's not designed to fire to spec. If you want the longest bulb life, and true color the bulb has to offer then you must fire them to spec. Certain bulbs fire best with specific ballast types. That may have been the topic you describe from other forums.

So when you decide to change your bulb, know your ballast type...pulse start, probe start, or electronic. Know the ANSI code, for example my lights came with a 400W ballast which has an ANSI M59, this ballast fires the XM 20K the best, if I had a M135, it would fire the Radium to spec. When experimenting, I got a M80 250W ballast, and it fires a Radium perfectly.

I'd say the majority if not all just replace their bulb. They only replace their bulbs and ballasts, when changing to a bulb that their current ballast wasn't designed to fire.

 

ahh ic.
thx