Marshall
Turtle Keeper + CPL(H)
This is my setup for turtles and has captions explaining why each element is designed the way it is because the entire project was built for turtles from the first shovel of dirt to flipping on the power switch of the pumps and filters. All of the features are just basic materials you would already have or easily find and the ponds ecosystem has just been tweaked a bit to suit their needs. I would imagine that if you can make a pond at all (and all of you seem to do very well at building a pond. Much better than my pond in most cases) then you could make a turtle sanctuary as well.