Electrical and safety

The blinds show outside. The inside can be plywood. Rooms tend to have windows. Not every one has a basement.

Can anyone tell me if its safe to put a 250 watt hps bulb into a 400watt hps system, or will it blow up the bulb or something?

U should be fine it's the same as taking a 100 watt bulb on ur desk lamp and slipping in a 30....no explosion.
The amp draw is created by the bulb........nothing else. ur ballast can DELIVER 450.... if necessary.

Good Luck.

out.