Recently, around three weeks ago (judging by my join date, I would say the 18th of February this year) my mother found an RES hatchling on the beach. It was actually on the steps leading to the beach and we suspect someone could have abandoned the turtle there, knowing someone would find it. There's no way for a turtle to get up there on it's own. Not only that, but the nearest fresh water source is a good mile away from there. My mom calls me telling me about the turtle and asking if I wanted to keep it. I really have no idea how it came to her decision to that. I love all animals and can't turn them down, my mom knows that. We would be overrun with pets if my influence were strong enough (it almost is. XP) We took the RES hatchling home in a small plastic container with a little water in it. I have changed the tank four times and it's only been three weeks, which is why I fear for stress on the turtle. The first two setups were very inadequate, it was before I fully realized what an ideal system for the turtle would be (this was after research
So I changed his tank again recently, hmm two days ago. We finally got around to taking out the 55 gallon tank and set it up and put him in it (oh forgot to mention that I have three neon tetras in the tank with him along with one glo-tetra. I don't know if this makes a difference. When I talked to this pet store lady she said adding fish could cause an ammonia spike, though we added ammonia remover or something to the water each time we cleaned the tank. I've had the fish with him for almost two weeks now, I think. Huh, time flies fast.)
Down to the main issue now. Along with my concerns of underbasking and stress, there are some other things I'm wondering about. I've done my best to research but never came up with a straight answer, really.
At first he was scared of me and would going into his emo corner when he saw me (well he still does that just less often now with the new tank) He seems to be getting used to me now and yesterday (Note: his tank is in my room, he doesn't bask while I'm in the room (I've caught him basking upon slowly entering the room so on days I know he didn't have the chance to bask I stay out of the room and when he has basked while I was at school. I just am quiet and I try to not make any too sudden movement while in the room and interacting with him. I know he watches me because when he slowly creeps to the surface at first I would get excited and sit up to see him better and he would dive down back in the water into his emo corner)) so while he used to stay in his emo corner while I'm in the room, he has started swimming a lot more when I'm there and its sooo cute but the problem is that yesterday I was taking pictures of him from my bed, so he didn't know and wasn't disturbed and luckily my camera has great zoom, but I saw he was doing something weird I hadn't seen him do before. He was sticking to the surface and seemed to be gulping air or something. With his head barely poked above the surface, his neck was inflating a lot like a bullfrog XP and then a few times when he would go underwater he would blow bubbles and he had bubbles all over him. He did it for a long time and I think he's doing it now. He just staying at the surface. I read things about respiratory problems but it said only on land. I barely see him on the and when I do I haven't seen him blow bubbles. It just seems kinda off and it has me concerned. :/ I don't know if it's normal. Though I haven't had too much experience with watching turtles swim, his swimming seems pretty even.
What prompted me to post this was when I was watching him and realized that the coloring, between what I believe is called scutes on the upper part of his shell, was off. Some research on it made me very unsure and that's why I'm posting it here. When I first got my turtle he had black between the scutes and now it's a light pink sort of color.
Answers to the prompted questions:
How big is your turtle? My turtle's shell is a little over and inch, though under an inch and a half.
How long have you had it? I've had the turtle for almost three weeks come Saturday.
What is the water temperature?Water temperature stays at 80F. I use a water heater and thermometer. I'm not entirely sure on the amount of water in the tank. It's a 55 gallon tank, not quite fully filled but close to it (I would have to lower the water line if the turtle was bigger). I am using a water conditioner and also a good filter. I'm not sure about basking temperature... I'm using a 75watt "basking bulb" the brand is Critter Culture. :/ I'm not sure what the heck it is, not label of UVB or anything. It's all they had at the store and I live in the middle of nowhere so I have to wait until I have time to go an hour away to the nearest pet store: petsmart. Unless this IS a UVB? Seems kinda sketchy to me. It gives off a real good amount of heat (enough to entice basking) and yes the basking platform is easy for my turtle to climb on.
I've been feeding him ReptoMin pellets (and sometimes, usually, he eats the fish food, TetraMin >.> then he begs for more and gives up fast and goes to his emo corner. I make sure to not overfeed him. Usually when he goes to the emocorner is when I feed the fishies so they eat their food before he gets there. XD) My turtle ate just a few hours ago.
His tank is 55 gallon. It's not near the window (should it be?) and the room is basically empty except for me and my dog who only is in at night and has no interest in the turtle. The turtle's tank is on a high stand so the dog cant even really see the turtle.
I did read the basic care section as well as a lot of others. I did research on this but never found definite answers. I may just fail at research...
There is nothing else that seems abnormal to me.
To sum it up I'm worried about possible underbasking, him blowing bubbles(??)/staying near surface more often (sleeping inside log thing that floats), and the change in his shell.
Below are pictures including one after I first got him and one that I took today:
This was the best picture I could find of his shell around when I first got him.

This is a current picture. I took it today, to show the shell better. I tried different angles but my camera didn't want to focus for some reason.

Best picture I could find of his belly. Dunno if it helps or not.

Shows his shell underwater and the bubbles

Up close of the bubbles on him



