Thank you for getting back to me. The rock is where you want the turtle to be. Turtles can hibernate under water, but I don't think this turtle was or is hibernating. to hibernate underwater, they need a thick layer of mud and leaves to settle into, and the water has to be pretty deep. Turtles normally cannot hibernate successfully in our garden ponds, and must be brought inside in the winter. When a turtle gets too cold, it will become lethargic. This is not hibernation. It often results in death because the turtle stops eating, stops surfacing for air, but is not in hibernation. A turtle can drown in this situation.
From what you have described, your turtle is near death, but it is worth trying to save him. I thought perhaps he was dead until you said he moved somewhat. The red feet are a bad sign. Redness on the skin is often a sign of septicemia - blood poisoning. It must be treated by a vet. You can read more about septicemia by scrolling down about 1/3 on this page:http://www.austinsturtlepage.com/Care/medinjuries.htm
This link will take you to a directory of reptile vets:
In the meantime, don't put the turtle in the water. The basking area should be about 85*F. If you place him there, his body will gradually rise to that temperature and he may become more active. There will be nothing more you can do on your own. If the warmth helps him become more active, but his feet are still red tomorrow, it would be best to make a vet appointment.
It's too bad you got your information on care from a pet store. Most people do. While we should be able to rely on such information, unfortunately, it is often wrong. They sell people the wrong lighting, advise the wrong foods, and often don't know the correct temperatures for the various reptiles. The clerks who work there do not really know very much about the animals they sell, but just repeat what manufacturers of products tell them.
I don't know if you'll be able to save the inactive turtle, but for the sake of the other one, I'm including my slider turtle care sheet. It will describe for you the conditions turtles need when we keep them inside during colder weather.
Since the turtles will be kept outside again eventually, I'll also give you information on that. Hibernation is a dangerous time, even for wild turtles who have adapted to outdoors and can find the optimal places for hibernation. For domestic turtles in man-made ponds, the risks are even greater. Turtles can suffocate, starve if they don't have enough fat built up, develop fatal bacterial infections if they eat too close to hibernation time, and be killed by toxins that build up in the water. There is no way to absolutely ensure that your turtle will survive the winter. There are ways to increase the chances that he will. There must be at least one foot of unfrozen water at the bottom of the pond. There must be something to dig in on the bottom, so an earth-filled box would work. The water must have adequate oxygen in it - turtles absorb it through their skin when hibernating. It's a good idea to have an electric de-icer on the pond's surface to allow oxygen in and the detrimental gases out. The following site has more details on turtle ponds:
Here is more on hibernation:http://www.redearslider.com/hibernation.html
The time leading up to hibernation is also risky. If you have an extended period of damp weather with temperatures in the 40's to 60's, the turtle will become less active, but it's not cold enough to trigger hibernation. Skin and shell infections and respiratory infections are common in those circumstances.
Besides hibernation, there are a couple of other problems you may encounter with outdoor housing. One is that your turtle is likely to simply leave. They go off seeking mates the first chance they get. A small fence a few feet out from the pond will be needed. Many people make a rock or concrete block wall just tall enough to keep in a turtle. Predators often injure or kill turtles that live outdoors. Raccoons are the most common offenders, and they will chew off feet, and destroy shells. Dogs will grab a basking turtle and carry it off, thinking it's a toy. We regularly have customers who are dealing with terrible injuries to turtles caused by raccoons and dogs. The site I gave you above on pond design has some tips to minimize these problems.
If you have more questions, let me know by clicking on REPLY. I hope you'll be able to save the sick turtle.
(The above answer is intended for informational purposes only. If your pet is ill, you should consult a veterinarian. )SLIDER TURTLE CARE SHEET
Well-cared for sliders can live 30 years or more.The Tank
It's recommended that a baby slider have at least a 15 gallon tank. By the time the turtle is 3-4 years old, it will need a 60 gallon tank, so it's best to get the biggest you can in the beginning. You can also use a large RubberMaid tote. That's not as pretty as a tank, but costs a lot less. Set up the tank so there's a land area and a water area. Put the basking light at one end so the whole tank doesn’t get too hot. You want the water to be about twice as deep as the turtle is long. If the turtle is two inches long, you'll want four inches of water.Temperatures and Basking Area
Turtles need certain types of lighting and need to be warm. Air and water that are not warm enough can lead to fungal and respiratory infections and unhealthy shells. Turtles must have a basking area where they can get out of the water, dry off, and bask in very warm light. The ambient air temperature in the tank should be around 75 *F (24*C) , with the basking area warmer still. Over the basking area there should be some sort of lamp that will take a 40-60 watt incandescent bulb (or you can buy a ceramic light fixture made just for reptiles). If you live in an area that has farm stores, you can buy a metal light fixture made to keep baby chicks warm for just a few dollars. Don't buy the accompanying bulb, however. You need an ordinary incandescent bulb in the basking light. Hardware stores sell similar fixtures as work lights. The basking area should be kept at 85-90*F (29 to 32*C). Use a digital probe thermometer to be sure. You can adjust the temperature by raising or lowering the light fixture.The lights that come with the covers on aquariums are not suitable for turtles. You'll also need a submersible aquarium heater that will keep the water 78-82*F (26 to 28*C).UVB Light
It's extremely important that you buy an additional light that produces UVB rays. A Reptisun 10.0 is a good brand that does. If you choose another brand be absolutely certain it provides UVB rays. Don't take the word of pet store personnel, but read it for yourself. Full-spectrum, DayGlo, sunGlo, UV, or UVA are not the same thing. I'm putting a lot of emphasis on this because it's crucial to your turtle's health. Without this light, Metabolic Bone Disease (MBD) will develop because your turtle won't be able to produce vitamin D. Vitamin supplements are not a good replacement for the proper lighting. MBD causes a very slow and painful death.UVB bulbs must be replaced every six months as they lose their effectiveness after that, even though they may still look fine. Light that comes through a window isn't sufficient because the glass filters out most of the rays turtles need to stay healthy. To prevent MBD, turtles also need calcium. The easiest way to provide it is to place a cuttlebone in the tank. Cuttlebones are sold in bird departments of pet stores.Filtration
Turtles are very sensitive to water quality. Even if you change the water every day, it can still contain harmful chemicals. A good filtration system is essential. Water changes are also needed even with a filter. If the tank is too small, no filter can keep up with the amount of waste that turtles produce. Feeding
Feeding is an area where pet stores often give out bad information. Commercial food should make up only 1/4 of the diet. Animal products (cooked meat, earthworms, canned cat food) should make up another 1/4. The remaining half should be plant foods (dark lettuce like romaine, bits of strawberry or melon, etc.). Hatchlings should be fed every day. Older turtles should be fed 3 times per week. Overfeeding can lead to gout and kidney failure. For Further Reading
This is among the most reputable sites on turtles.http://www.austinsturtlepage.com/Care/caresheet-red_ear_slider.htmMsAM41038.1331376505