red-ear slider

Question
My daughter was given 2 very small turtles that we have identified as red ear sliders. Although we said thank you for the gift, we could not find anyone to take the turtles that was knowledgeable of their care. So we went to the internet. We set up the aquarium, change the water and offer a varied diet. We were told to feed them guppies, just to put them in the aquarium and well things were fine until one of them died. As you can imagine my daughters frustration, it broke her heart as she cried herself to sleep. As moving as this may be, I obviously have questions. One, the turtle that died, had a very swollen neck and was fine yesterday, my guess was it choked on a guppy that was to big for it. But again I am not an expert. Two, the other turtle has a rather soft shell and even has an area where is seems to be cracked. We took the turtle out of its aquarium just in case it was bacterial and are keeping it warm. I guess my main questions are if you can forward a safe home information we would love to get it help, no creature should be given to a family to FIGURE out what to do. Or if you can offer some care advise to help get him/her back to health. We are willing to do all we can but do not want this poor turtle to be in pain or misery. I can not find a vet close by to take it too for care or advise. So I feel I am somewhat stuck. Thank you for your time.

Answer
Hi Chastity, I can only assume that the person who gave your daughter these had no idea what they were getting you into. I can hardly think of a more inappropriate "surprise" gift then two sliders. They start small but they get large and require a significant investment in space, equipment and maintenance. The females will grow to the size of dinner plates while the males are just a little bit smaller. Their adult accomodation requires something in the 75 -100 gallon size with significant filtration. They can live for 30 to 40 years.

Temperature is probably the single most important factor in keeping sliders healthy.It is not clear from your question what (if any) type of heat sources were provided. Too cool water temperatures and inaequate basking site access and temperature severely compromises their immune system and can lead to a host of infections. Their immune system and all other metabolic functions are powered by access to this external heat source. They need to be able to leave the water to dry and warm themselves. I have linked one of the most complete sites on turtle care that outlines what they need in terms of water and basking site temperature etc.. My first suspicion regarding the death would also be bacterial infection. The soft shell and crack on the second one would suggest nutritional deficiency or infection as well.
Nutritional deficiencies are also common with sliders. A varied diet should include and be centred around a good quality commercial pellet designed for aquatic turtles. This will ensure a good basic, balanced level of nutrition as a starting point. I use Reptomin and Mazuri. Fish (guppies and rosy minnows) earthworms, snails etc can then be added to round out the diet. A cuttlebone (sold for pet birds) can be placed in the water as a additional calcium source. You can add more plant matter to the diet as they mature but babies are highly carnivorous. Again, they will need access to the proper temperature to effectively metabolize their food. Sliders also need to be in water to eat.
Sliders are farmed in the U.S, produced in enormous numbers and sold cheaply. They also die in enormous numbers from mis-informed,indequate and indifferent care. It seems people have come view them as disposable, temporary pets. This one sounds rather lucky to have landed in your care even if you probably don't feel the same way!

http://www.austinsturtlepage.com/Care/caresheet-red_ear_slider.htm

http://www.austinsturtlepage.com/Care/medshell.htm