(My questions are: Do I get an aquarium with a hood? I don't have any experience with large aquariums but how many gallons will keep him/her happy? I would rather get a large enough one right off the bat. Also, he/she does not come out of the water to the basking area. Even if I put him/her up on it, he/she goes right back into the water immediately. Won't this cause some kind of shell-rotting problem? The gal at the pet store sold me a red bulb for the basking light telling me it wouldn't interfer with the day/night cycle. Do you think maybe the RES dislikes the red light? (I know now after some reading I need to get a UVB light). Finally, I have had the turtle for a week with no water heater. I'm concerned about the length of time he/she can be in room temp water)
I am very sorry you had such a bad pet store experience.
I would say no dont get an aquarium with a hood. An aquarium with a screen top is much better as you can put the lights wherever you want.
You didn't say how big your turtle is but since you bought it at a pet store i will assume it is at least 4-5inches. In this case i would go with a 50breeder or larger aquarium. I like the breeders the best because they are wide and allow for the turtle to turn around, even when he gets bigger (and he will). 75gallomn tanks work really well also, and will be a great permanant home.
As far as basking, i agree with the above, once your turtle has had a change to calm down and adjust to him new surroundings you may see him basking mroe often. But i am sure he basks when you are not around
As far as lighting goes: you want a basking spot (out of the water) to be between 85-90degrees, use a dome lamp with a bulb of appropriate wattage on top of the screen. It doesnt matter what color is it, red or otherwise. Also include a UVD bulb, remember that for UVB to be effective the turtle has to be able to get pretty close to it, at least within 10-12inches.
Room temperature water is ok unless it gets REALLY cold in your house.
Make sure you give your turtle a well rounded diet of turtle pellets, veggies (collards, mustard greens etc..etc) and insects. Also you can buy frozen beefheart and brine shrimp and silversides at the pet store, these work nicely as treats. And just in case the petstore mis-informed you on this too...your turtle does not need goldfish. Goldfish are dirty feeders and really shouldn't be fed to anything, he can get all his needed protien from insects (crickets, earthworms, super worms..etc) and from frozen chunk fish food.
Good luck!!
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0.1 Bearded dragon
0.1 mexican kingsnake
1.0.2 Leopard Gecko's
0.0.1 Rose Hair Tarantula
1.0 BTS
0.0.1 Reverse Okeetee Corn
0.1 Bullmastiff
4.1 Cats