Are clogs in the AC condensate drain common in Florida?
I live in South Florida and I too have to do this. My house has 2 AC systems. One of them clogs up after about 3-4 months, the other never has. I'm not sure what the difference is, but ever since I started putting a bit of bleach in the condensate line every time I change my filters; I've had no clogs since then.

Assuming this is actually your problem, I would suggest that you do the same.