Bumping this old thread because I have just started construction on a sequel to this vivarium!
I moved to a new apartment this past summer. The tank was impossible to move with the land area intact, and the silicone holding the land area retaining walls in place had started to give out anyway. I chose to remove the landmass entirely, and ever since my turtle has been stuck with a barren tank containing only a 'floating turtle dock' for land. Needless to say he has been giving me the dirty eye ever since.
You can see above where the plastic had begun to separate, and how the cork paneling was falling apart. For those wondering, the cork lasted about three years fully submerged before it began to disintegrate.
I have been planning the second coming of this tank since around November. My primary goal is to correct a flaw with the original design: the land mass wasted a lot of swimming space. By creating a wall, I had a land area that was as deep as the water, roughly 14 inches. This is far more soil depth than the plants needed for rooting, and wasted a lot of space that could have been used for swimming.
As shown above, the big change to the design is to move to a shelf for the land, rather than a full wall. This will open up a lot of space under the landmass for swimming area, and provide a nice dark underwater cave for the turtle to sit in when he should feel so inclined. The shelf will be supported by two log columns.
Aside from this change, I am preserving the main layout: a lowered "beach" that will be slightly below the waterline, making it easy for the turtle to climb out. This will be filled with gravel and rocks, and have some focused light for sunning. A few inches up from that will be the primary landmass, which will be filled with soil and planted. As before, the front of the landmass will be covered with cork, and this time I will also be covering the back wall of the tank. I'm hoping some climbing plants and moss can utilize this as a growing surface.
I built the first prototype out of acrylic, and quickly realized that it was unable to span the distance between the two columns without bowing. Unable to source a thicker plastic locally, I talked to my father about using wood (he is a boatbuilder and lobsterman in Maine). He said that I could easily expect several years of structural integrity using wood, so I moved ahead with that.
The platform was constructed out of three pieces of pine: the shelf bottom, front, and a divider between beach and land areas. I used stainless steel wood screws and Gorilla Glue to attach the pieces, and then sealed the seams with silicone.
Next I cut some cork panels, and attached those to the front of the shelf with finishing nails and Gorilla Glue. I left an angle where the land and beach join, to help disguise the transition. You can see above the finished shelf sitting on the log columns.
Tonight I intend to borrow a small tank from a friend as a temporary space for the turtle, so I can drain his tank and mount the shelf. I have some new coconut fiber for the land, but still need to source some gravel and rocks for the beach.
If you'd like to follow a long, I'm publishing information on my Aquarium blog (I also use this for my reef tank, so expect a bunch of mixed information), and I will update this thread as I go!