why is the water in florida by the atlantic ocean green-blue and inthe
northeastit is brown color

The brown colour is from suspended soil particles in the water. There
are more and bigger rivers on that side, and the Gulf of Mexico is a
smaller body of water than the Atlantic.

The blue-green colour is partly (probably mostly, actually) a
reflection of the colour of the sky, and partly minute algae giving
the water a tinge of green.

I think it could be different colors of coral in the water along with
the water being warmer in the south. The warmer water will make the
greenery grow more producing more oxygen, thus clearer water

Cleaner water from more healthier plants producing more oxygen?!?! I'm
guessing that you aren't a scientist of any sort. First, cold water
has higher levels of dissolved gases, second, what is the link between
clarity of the water and dissolved, colorless, gases?

From what I understand, the difference in color in the ocean from the
Equator to the North Atlantic is caused by the angle of the sun to the
Ocean. That is to say, a combination really of suspended particals and
sun angle. As the suns light hits the water, it reflects the light
back to your eye, and depending on the angle at which the suns light
is reflected to your eye, will determine the intesity of blue that you
see, or the intesity of light reflected back to your eye. So if I can
clear it up better, the higher in the sky the sun is, the more blue
light is reflected to your eye, due to refraction of light thru water,
the lower the sun is in the sky, the more light is absorbed and not
reflected to your eye, thus a darker color..