I am thinking of doing a reef tank outside

[Mini4x]

Just plumb it so you can take it offline in the winter and drain it, not like you're going to be out there to enjoy it in the winter much anyways.

 

[tigerslacrosse4]

What if you were to screen in this deck of yours??? But at the same time make it so you can have windows that replace the screens in the winter almost like a storm door??? then you would be able to protect the tank from some of the elements. Like people are saying how are you going to keep the tank cool on a day where its 85 plus degrees????? you have to think of all the variables that have to be perfect for a stable system and compensate for them. In the winter you should have no trouble with it being cold with the glass in place... just an idea I think that would be really cool but also really expensive to upkeep and even get started! You should take a peak at the TOTM section of this forum there is IIRC a tank in a greenhouse looking room in there and that could be another option for you if you want to make this happen good luck Orion!

 

[The Ng Thing]

Mini4x I was thinking the same thing. Have two tanks connected together in the summer and isolate the outside one in the winter. Sort of like dog kennels, where the dogs have the choice of going outside/inside. This looks do-able if you win the mega-millions =P