Hold on, please, before adding more stuff... Phosfree is not generally recommended around here (it is unnecessary if you maintain adequate levels of chlorine). And why would you want to add more calcium, when you already measured more than adequate CH at 310?
What was your test result (with your own kit) for TA? And, if your testing now confirms 0 FC, it's important to get some chlorine in ASAP, so algae is less likely to take hold, and to keep the water sanitary if you are still swimming. Being in Florida, I imagine your swim season isn't over just yet...?
The fact that your pool service used liquid chlorine helps explain why you have quite reasonable CYA levels at around 30 ppm. Liquid chlorine (aka bleach) is the usual recommendation under the method taught here. The problem with all powder forms of chlorine (indeed they do seem so much more convenient, as you point out) is that they always add other chemicals along with the chlorine. If you use cal hypo powder, you will continue adding to your CH numbers. If you use dichlor powder, you will continue adding to your CYA. Chlorine is a daily consumable. Calcium and cyanuric acid are not -- they accumulate in the water over time, and eventually cause problems that can really only be addressed by dumping some of the water in the pool and replacing with new water.
Please get some chlorine in the water (using liquid). We can advise you about quantity, if you like, or you can determine it for yourself by going to PoolMath (link at the top of every page on the site).
http://www.troublefreepool.com/calc.html
Then, before you add anything else to the water, consider taking a bit of time to read here on the site. Here are some suggestions to start with:
Pool School - ABCs of Pool Water Chemistry
Pool School - Chlorine / CYA Chart
Pool School - Recommended Levels
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