u/ButterscotchFew972

So background information: this turtle was a friend of my grandma's and grew up in a tiny 10 gallon tank (his shell is like 5 & 1/2 inches) we got him a new ~ 55+ gallon tank (i read that you're supposed to have 10 gallons per inch of shell) and have ordered stuff for said tank (said stuff hasn't arrived yet). This turtle was just dropped off on us and i've never had a pet turtle before, so i'm wondering if these lighter marks on his shell are normal or something that needs attention. I would also appreciate tips on taking better care of him if you have any! Thank you!