baby RES is lethargic

Question

Baby, "Harry Potter"  

Malfoy   I recently purchased a baby RES and at first it was very energetic and now he seems very lethargic. It basks all day and won't swim and I'm pretty sure it's not eating now. When he did eat, it gets fed hatchling formula and brine shrimp, usually in the morning. He will occasionally pick his head up and look around. I'm not sure of the last time he  defecated. He shares a 10 gallon tank with another RES that's a little bit older (last Halloween). The lighting is the light that came with the tank. Humidity I am unsure, the temperature is a little above 75. I'm thinking of bringing him to the vet to get him checked out. I was just wondering if before I do that if this is normal (the other RES is very active) and if it's not what I can do to help.

Answer
No, this is not normal and you need to take him to the vet. That's all I can offer you since you didn't answer the questions in the instructions properly. If you can't look over that light and tell me what it is, whether it's UVB or not, or what your basking temps are...then I can't help you further.

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