Floating red eared slider

Question
I gave my slider kitten chow, I no other food at the time.  I have two questions. First, since I gave him the kitten food he seems to be floating.  He is fine but can't get under the water, he normally doesn't come out.  Second how long can he go with out food. He is 10 months old and is roughly 3 or 4 in wide.

Answer
Floating can be pneumonia or digestion issues. If he is lopsided, pneumonia. If tail-end high, digestion problems.

Pneumonia can be tough, even for experts. Be prepared to see a vet for supportive treatment.

In the meantime, boost temps in the water to about 80-85F and reduce stress.

Also, check out a good site like http://www.redearslider.com or http://ww.austinsturtlepage.com for general care ideas- I suspect that the reason the turtle is not eating well is that there is a glitch in the cares.