Unusual results. When hardness is 60 alkalinity is usually higher than 10 ( I would guess around 25 min.) . An alkalinity of 10 is to low for a fertile pond. You need 20 at least. Ask your county ag agent about your area.

I am guessing about what is up. Two guesses. Mostly acid water in the pond (from the acid dirt) so you have a low alkalinity but the water (ground water or from a well ?)is from a Fla limestone aquifer and thus has hardness which is in the top water layer if that is where a well dumps it. Or second (I doubt this one) the pond water has natural hardness and the well/ water source has low alkalinity (acid character). See the following :

http://srac.tamu.edu/tmppdfs/13452410-46...ebb6b2d5a43a5f3