@the reptile guy At the moment, I am between turtle enclosures as we recently moved and everything “turtle” (and fish) is on hold and temporary. Right now, I have them in a large cinderblock enclosure, 2 courses tall. When their habitat is re-done, it will have 2 or 3 rows of 8” pressure treated lumber, running horizontally. They are free to roam anywhere within the habitat, and I have it fixed up with multiple micro-climates. They have dirt piles to dig in, a nice mud-hole (that they dug themselves), plenty of man made tunnels, as well as overturned terracotta pots as “hides.” For now, they have multiple 14” plant saucers for water, but they will eventually have their own bog with circulating water. The only time they are “locked up” is during brumation time (in another month) — and when we had Hurricane Laura a few weeks ago. They have large tubs in the garage to brumate in for now, but once their new habitat is completed, they will be free to put themselves up at night, in whatever manner each one prefers — and each one has a favorite spot. Again, I offer all kinds of micro-climates and hides for them to feel safe. Have never had an issue with critters, though once, many years ago, I went outside to do a PM check on them, and found an opossum curled up in their habitat. It was gone next morning.
There is no need for anything heated. When our nighttime temps stay consistently in the 40’s - 50’s, they’ll go into their brumation tubs where the temps will hover in the 50’s until time to bring them up in the Spring. My 2 biggest challenges are keeping them cool in the heat of summer, and keeping fire ants out of their habitat.