I just purchased a 250 watt ceramic heat emitter for my coop that is 12x4x8. My dh is very worried that the 250 watts is too warm for the coop. The temps get as low as -20F or more. I'm not planning on using the heat lamp until it gets really cold and subzero temps. We are only needing the coop warm enough to keep the water from freezing. Is my dh right? Is the 250 watt too warm? Should I resell the ceramic heat lamp and buy a 100-150? This is our first winter with our chickens. We are boarding up 3/4 of the run, so they can use it all winter. I can't imagine them getting along peacefully in the coop alone. My RIR can be a big crab at times. Thanks.