I've been pet sitting a friends turtle. Was meant to be for a year but it's been about 2 so far. They gave me the instructions to feed a couple of the cubes of the frozen turtle food once a week and take it outside for sunlight every now and again. Normally once a week. I was doing that but I noticed some lighter areas on its back. There is some scales slightly lifted on the sides and on the belly. The belly has flaked off pretty much and the stuff underneath is not soft but not rock hard either like the top. I googled shell issues when I saw the lighter colour on the shell. Its always had a bit but I just got worried. I went to the pet store and they recommended a UVB light, a dissolving tab that helps with calcium and water conditioner. I've scrubbed out the tank again and done everything they said. I’m not sure if this is normal shedding. The belly part feels excessive. I was told by the pet store to feed every couple of days and I started increasing food straight away. It's active and happy to eat. Any advice? I don’t know what I'm looking for or what else to do apart from a heat bulb. I never see it out of the water though.