I have twp red eared sliders that I took in for a friend of a friend yesterday. There's a male and a female, both a little smaller than my hand, and she's shorter than he is, but just about as wide. They're both in a (pretty sparse) 55 gallon tank. It's got a stick-on-the-wall dock for basking, a hollow floating log, and an underwater arch.
Is this tank big enough for the both of them? They seem to get along well. He doesn't seem to mind the size of the tank. He mostly chills inside the log and paddles it into the current from the filter, and pushes all the lettuce off the dock and into the water. But I'm watching her do these long swims back and forth, and then push against the sides of the tank. And, if I'm understanding what I've been reading correctly, they should actually be in a tank about twice the size? Two five-ish inch turtles at ten gallons per inch per turtle?
And then, some general questions. How often should the water get changed? They're both shedding like crazy right now. Should the water be clear, or should I expect a little cloudiness? Should I put more stuff in there for them, or will they just feel crowded in a tank this size? What about water plants?
What do I use to clean the inside of the tank? I assume I should avoid ammonia cleaners. Is white vinegar safe?
And smell. I've been told to expect that there will be a swampy sort of smell. It doesn't seem to me that a clean tank should smell like a swamp.
We had a red eared slider when I was growing up, but my mom did most of the actual dirty work. Cleaning the tank and changing the water and everything. And there wasn't much that needed to be done, because my dad had built him this little indoor pond ecosystem thing full of plants and such.

