This is a bad thing I had a huge torch coral that my clown started hosting nothing happened to the clown. but the torch eventualy got tried of it and died unfortionitly I was not home all day and lost most all my corals .. Lesson learned the hard way .. Get um out
I have my chiller outside the window plumed into the tank had it for years like this no problem it's the same as having an AC window unit plus my house stays cooler and my chiller stays on way less the it use too .. Go for it you won't regret it !!