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How big is your turtle? 5.1 inch
How long have you had it? 1 year

What is the water temperature? 29 Celcius
Did you use a thermometer? yes
Are you using a water heater?no
How much water is in there? 180 Liter
Are you using a water conditioner? no
Are you using any filtration? yes

What is the basking temperature? 30
Is there a basking light? no
Is there a basking platform that is easy to climb on? yes
What kind is it or what is it made out of? rack for shoes
Is there a UVB light? no

What have you been trying to feed it? pellet and jello shots
When was the last time your turtle ate? today in morning

How big is the tank/pond/enclosure? 53 gallon
Is the tank near a window? yes
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

Is there any other unusual activity/symptoms? no

if its not fungus it might be trapped air in the shell from shedding is it shinny like gold or copper?

its white spot here the image

It may be some sort of fungus or yeast infection. If it isn't too deep it may simply shed off with the next shed. Are the white areas smooth and flat with the surface of the shell, or are they rough and do they feel like the white is eating into the shell?

Of more concern to me is the area where the scutes come together - the seams. The seams look sort of black and eroded in the photo. Are they wet or smelly? It's kind of hard to tell from the picture but it's possible there's some infection along the seams.

It does look like that turtle's due for a scute shed. The photo you provided is in good focus but it looks like the turtle is wet. Can you get a photo of the shell when it's dry? Get as close to a seam as you can without losing focus - it is important to keep good focus.

I can see that the basking area is above the water line but it still looks wet - perhaps because of water splashing on it from the waterfall. If so, this is not good because it's essential for shell health that the shell get to dry out completely - top and bottom - at frequent intervals (daily). The turtle needs to be able to bask on a totally dry place for several hours a day. If that's not happening now, can you rearrange things in the tank to be sure he gets a dry spot?

My bigger turtle also has the same whitish spots/blotches all over the shell. It's really apparent when she dries off.

yeah its turn when my turtle dries off, musa has white shell after him dried off. Lot have white spot. its smooth not smelly. later i am going to upload it. Lot dried shell and must focus. ok...