The tomatoes developed by UF are listed here in this document: http://edis.ifas.ufl.edu/pdffiles/AG/AG21300.pdf. They grow great here, they just don't taste great. Some tasty hybrids do well here - just not growing in unamended soil in the ground.
Chloramine, on the other hand, is a combination of chlorine and ammonia. While chlorine dissipates and evaporates into the air relatively quickly, chloramine is more stable and will last longer in the water system. The goal is to provide increased protection from bacterial contamination.
Q. What is Permex?. A. Permex is a patented rubber compound that is formulated to withstand the deteriorating effects of ammonia and chloramine which are often used in water treatment facilities and cleaners. Q. What is Chloramine?. A. Chloramine is a combination of a chlorine and ammonia reaction in water.