250w HPS bulb in 400w MH light

[Billpopy79]

I've been given a 400w MH light with a blown bulb.
I have a brand new 250w HPS bulb, can anybody tell me if this is safe to use or will the ballast overpower the lower wattage bulb.
Thanks

 

[Old Salt]

Unless it has a dimmable ballast, she'll blow.

 

[Billpopy79]

Ah I thought as much, thanks for the info.
Think I'll stick to the led's for now.