redearslider.com

I have had turtles for years now and I never really had a problem like this before so I don't know if its normal or if I should worry about it. I have 2 baby red ear sliders but ones shell is getting darker on the top in certain areas.

How big is your turtle? Just a baby 1.5 - 2 inch shell length
How long have you had it? Since about November (5 months-ish)

What is the water temperature? 75
Did you use a thermometer? Yes
Are you using a water heater? No, my house in generally hot
How much water is in there? 2-3 inches high
Are you using a water conditioner? I use calcium blocks which also condition the water
Are you using any filtration? Yes

What is the basking temperature? 85
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? Made out of rocks
Is there a UVB light? Yes

What have you been trying to feed it? I feed them regular turtle pellets and sometime things like lettuce as well
When was the last time your turtle ate? Today, both my turtles eat well

How big is the tank/pond/enclosure? Not sure; Its a 55 gallon turtle breeding tank I bought used from a local pet store
Is the tank near a window? Not really but is in a small room like 7 ft away from one
Is the tank in a room with a lot of activity? No

Have you read the Basic Care section? Yes
Have you searched the forums for similar situations? Yes; but im not sure what exactly what it could be

Is there any other unusual activity/symptoms? Nope he seems fine

It looks like algae... have you ever tried cleaning his shell?

Yea I just tried taking it off with a toothbrush and it didn't work. I'm thinking that he's getting ready to shed on his shell but i'm not sure.

My turtle has this too. Looks like algae growing under some of the scutes. I think it should go away with a shed.

oh ok thanks, he should be shedding soon

I would still consider a water heater, to help keep the temperatures consistent. I would also look into increasing the water level and switching to a different substrate. We also don't recommend the white turtle blocks as they are not proven to serve any real benefit.

Just to update on this: The darkness on his shell just kind of just went away and faded on its own. He looks normal and is doing just fine now.

Thanks for the update.