Hell everyone. I'm somewhat new to the large aquarium scene and i need some help. I'm thinking about building a 1000 gallon outdoor pond but i have a few dilemmas. First off is the water temperature. I'll need to keep it in the mid 70's, even when it's around zero degrees outside. I'm looking for some insight on how to keep the water that warm all year. I'm also wondering if it would be better to dig into the ground or build up off the ground. Which would help keep the temp right and the cost of building down? Any more input would be greatly appreciated. Thank you.