Spot on shell of small turtle, and feeding questions
Hi I'm new here. I have a couple questions. My daughter won a RES at the fair about a month ago. It seems to be doing well so far, except s/he has developed a spot on it's shell that has be a bit concerned about shell rot. Also has a lighter area down the raised ridge down it's back... could that be a scratch? It likes to try to hide behind the filter and maybe scuffed it? I tried to get a picture, hopefully you can see the area I'm concerned with:

Its the spot about halfway down on the right side of it's shell. It seems to be very alert/active. The shell is a bit soft all over, but I read in baby turtles that it's normal to be a bit pliable.
The other question I have is food. We had been feeding him/her food sticks from a little baggie my parents got with the turtle at the fair. We ran out of that a couple days ago and started feeding TetraMin baby, but I don't think s/he likes it. S/he will act hungry, but when I put the food in this morning, s/he took a bite, spit it out and swam away. I had my husband get some regular adult TetraMin floating sticks, and s/he is eating that better. Will that cause any issues?
How big is your turtle? Maybe about 2"?
How long have you had it? About a month
What is the water temperature? not sure... warm to the touch
Did you use a thermometer? no
Are you using a water heater? not in the water, we have a heat lamp above the tank
How much water is in there? almost 4" deep, about 1/3 up the height of the tank
Are you using a water conditioner? Yes, ZooMed Reptisafe
Are you using any filtration? Yes
What is the basking temperature? not sure, no thermometer
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? Plastic one that came with the tank
Is there a UVB light? Yes
What have you been trying to feed it? ReptoMin floating sticks
When was the last time your turtle ate? This afternoon
How big is the tank/pond/enclosure? 20" long, 10" wide, 12" tall
Is the tank near a window? Next to it but doesn't get light from it
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? No, seems to be active/alert and doing ok otherwise.

Its the spot about halfway down on the right side of it's shell. It seems to be very alert/active. The shell is a bit soft all over, but I read in baby turtles that it's normal to be a bit pliable.
The other question I have is food. We had been feeding him/her food sticks from a little baggie my parents got with the turtle at the fair. We ran out of that a couple days ago and started feeding TetraMin baby, but I don't think s/he likes it. S/he will act hungry, but when I put the food in this morning, s/he took a bite, spit it out and swam away. I had my husband get some regular adult TetraMin floating sticks, and s/he is eating that better. Will that cause any issues?
How big is your turtle? Maybe about 2"?
How long have you had it? About a month
What is the water temperature? not sure... warm to the touch
Did you use a thermometer? no
Are you using a water heater? not in the water, we have a heat lamp above the tank
How much water is in there? almost 4" deep, about 1/3 up the height of the tank
Are you using a water conditioner? Yes, ZooMed Reptisafe
Are you using any filtration? Yes
What is the basking temperature? not sure, no thermometer
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? Plastic one that came with the tank
Is there a UVB light? Yes
What have you been trying to feed it? ReptoMin floating sticks
When was the last time your turtle ate? This afternoon
How big is the tank/pond/enclosure? 20" long, 10" wide, 12" tall
Is the tank near a window? Next to it but doesn't get light from it
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? No, seems to be active/alert and doing ok otherwise.