Use common sense. It's only 400 watts, that's 4-6 regular light bulbs depending on what you have in your regular house lamps. You can easily keep the bill the same if you conserve a tad, and I mean a tad.

A fan is 10-20 bucks, get one.
tadaa Reviewed by tadaa on . Temp and Cost Ok, i was wondering, the temp when my 400W hps is during the day goes up to about 90d F. I know thats high, but there is no way i can get it to lower, without buying a fan (which i do plan on doing, but i have no money at the moment) will the effect my plant in anyways? its about 1.5 months in to flowering. And also, im worried that the 400w hps is costing me a BOMB. We dont get another elec bill untill april, so i cant find out how much its costing me so far. Can anyone tell me if they Rating: 5