I bought my first red eared slider about a month ago. Today, while changing his water, I noticed a faint pink shade around the bottom of his shell. Is this shell rot? If so, it doesn't seem to be very severe... yet.... what do I need to do to heal him and to prevent this from happening again in the future? I've attached a picture of both the bottom and top of his shell. Does anyone see any potential problems with the top? I look forward to the replies, this is my first post but I've been browsing these forums anonymously for months. I'm excited to be a part of this community.