| 84-86 is WAY too high for a reef tank! The key to success in a reef tank is stability...there may be a degree or two swing from season to season in the wild, however they are VERY gradual! Try to get a chiller that is operated on an elcirtonic temperature controller...like a Ranco dual...it controls the current to both the chiller and the chiller..only allows one to operate at a time! | 
