Hey all,
Basic details below.
I inherited this turtle a few months ago. He was eating whenever food was presented, swimming a lot. For the past week he's been doing nothing but basking and hopping in the water for very short periods. Also has not eaten in that time.
I've also noticed that his shell is developing what look like black burn marks between his scutes. Basking temp is in the mid 80's.
Any ideas?
How big is your turtle? 6"
How long have you had it? 3 months
What is the water temperature? 74 degs.
Did you use a thermometer? yes.
Are you using a water heater? no.
How much water is in there? 60 Gal.
Are you using a water conditioner? no.
Are you using any filtration? Yes. Ehim 350.
What is the basking temperature? 84 deg.
Is there a basking light? yes.
Is there a basking platform that is easy to climb on? yes.
What kind is it or what is it made out of? unsure.
Is there a UVB light? yes.
What have you been trying to feed it? Pellets, kale, collard greens, feeder fish.
When was the last time your turtle ate? ~1 week ago
How big is the tank/pond/enclosure? 65 Gallon. 36x19x24
Is the tank near a window? no.
Is the tank in a room with a lot of activity? yes.
Have you read the Basic Care section? yes.
Have you searched the forums for similar situations? yes.
Is there any other unusual activity/symptoms? Won't eat, basks all day.

