With the hurricane season coming up, I've been considering getting a chiller, since my generator's not big enough to run my AC, but it can easily run a chiller. It would also allow me to use a little less AC when I'm not at home. My question is, what size chiller would I need for a 55g tank to lower the temperature probably not more than 10 degrees F? I found a 1/10 HP at That Fish Place for a pretty good price. It says it'll lower the temperature of a 55g by up to 20 degrees. Is this probably an optimistic estimate on their part?