Thank you for getting back to me. It's very difficult to tell when a turtle is dead, but most of the time, when the body is partly inside the shell, the turtle is alive. I can tell that you care about your turtles, and want to take good care of them, but someone (probably a pet store clerk) has given you bad information on how to do that. If you want your turtles to be healthy and live a long life, there are some important changes you'll need to make. I'll give you a basic summary of slider turtle care, and then we'll talk about the sick one. The very first thing you need to do is create the proper conditions, which I'll describe.
It's recommended that a baby slider have at least a 15 gallon tank. Set it up so there's a land area and a water area. You want the water to be at least twice as deep as the turtle is long. If the turtle is one inch long, you'll want two inches of water.
Turtles need certain types of lighting and need to be warm. Air and water that are not warm enough can lead to fatal infections. 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, 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. The basking area should be kept at 85-90*F. Use a thermometer to be sure. You can adjust the temperature by raising or lowering the light fixture. If your tank is small, set up the basking area at one end - you don't want the entire tank to become too warm. A lack of a basking area also leads to illness. 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.
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, UV, UVA, DayGlo, daylight, and SunGlo are NOT the same thing. I'm putting a lot of emphasis on this because it's crucial to your turtles' health. Without this light, Metabolic Bone Disease (MBD) will develop because your turtles 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.
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.
Feeding is another area where pet stores often give out bad information. Commercial food should make up 1/4 of the diet. Animal products (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.)
Since you are a new turtle owner, you may want to look at this site for additional information on care and feeding. http://www.austinsturtlepage.com/Care/caresheet-red_ear_slider.htm
I would recommend that you provide the conditions your turtle needs as soon as possible. Without those conditions, turtles are likely to die, no matter what pet store personnel may have told you. At the very least, buy a basking light and thermometer today so you can get the habitat to the proper temperature. Then buy the other equipment as soon as you can.
Providing proper lighting and temperature may help with the sick turtle, but it would be best to have the turtle examined by a reptile vet, who can diagnose the problem with certainty and prescribe proper treatment. If you need help finding a vet, give me your zip code and I'll locate one for you.
If you have further questions, or want help locating a vet, just let me know by clicking on REPLY. I hope you enjoy many years with turtles.
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