RES Basking?

Question
I have 2 Red-ear Sliders one 10 inchs the other is 9 inchs. I have them in a 55 gallon tank that they have outgrown with a large Zoomed floating dock for basking they are to big for it. I have just moved and im going to buy them 125 gallon tank. What can I buy or build for them to bask on? I prefer to buy if possible!!!

Answer
I applaud you for not wanting to just set them loose in the wild when they grew up, and for being willing to spend the money. That's good. But the flip side is that even a 125 gallon is not big enough for 2 adult sliders to live in. As a temporary measure over the winter, or for display purposes in a zoo setting, yes. But to live in permanent, no. The filtration alone you must have to keep that water clean is staggering. I recommend 100+ gallons to people who are keeping one adult slider. Once they hit that dinner plate size mark, they need more space than that, for exercise, for de-stressing, and for other health related reasons.  

Sliders this big really really need to be in an outdoor pond. You can use a hard sided above ground kiddie pool for that too if you don't want to dig or build a big pond, and right now we have in fact picked up some of these pools on sale since summer is ending. We just bought a 430 gallon kids pool from Dollar General, on clearance for $3. It's the flip up kind with flat flexible sides, 8ft in diameter and 18" high. The kind you air up won't work because of course the turtle's claws could rip right through them. There are plenty of these pools around on clearance at home and garden stores, department stores like walmart, or dollar stores.

You can fill these pools with a bit of river pebbles at the bottom and add water, and what we use for large basking surfaces is flat pave stones from somewhere like Home Depot, Lowes, etc. Luckily, we live in a part of Texas where finding these large flat rocks is easy too. You can build up the rocks and gravel in one area above the water to place these basking rocks. We also encourage making part of the habitat completely out of the water too, as in the wild Red Eared Sliders leave the water for dry ground too. You can build up one side of the habitat with gravel which slopes up from the water, and makes a dry beach area.