The pump you are talking about is called a dump or purge pump, I guess if you are in Florida, they are not readily available on your hardware store shelf because you do not live where evaporative cooling is used. Where I live, you can buy one at any big box store.
You need that purge pump to help eliminate the mineral content in the water.
If you are having problems with the main supply pump, any good contractor should be able to install a good high capacity submersible pump to take care of that issue.
Freus units are not turning out to be what everyone expected, they are very problematic and if you want to save yourself any future headaches, go ahead and have the unit replaced.
I take it you have a dual compressor unit that is running two seperate systems?
I am surprised to see that one of these things made it all the way to Florida, I thought they were mostly used out here near the west coast.