ballast electrical question

[hillegom]

Thanks everyone for all the help.
And thanks to mike 31154 for the links, which convinced me not to use the 400 watt ballast.
The link said that if you used a bulb that was not rated for the ballast, whether bigger or smaller in watts, then you would decrease the end of life of the ballast.
So I will be wanting to trade this 400W ballast with capacitor for a 250W ballast. Will post tomorrow.