Yes, the Sunshine State does have temps higher than the Aloha State, so I am glad to hear you have no issues, hope all stays that way. Re insulation, please keep in mind that the purpose of insulation is to reduce the rate of heat transfer from the hot side to the cold, given enough time the temperature will be equal on both sides. This will definitely happen under the tank in a relatively short time, on a 30 degree (90F) day I would guess much less than half hour.