Total hardness and Calcium hardness are not exactly the same thing, but are close enough to give us an idea, if the pool store test is to be trusted. We generally find pool store free testing to be worth about as much as you think your paying for it, If you want to see this for yourself, get a water sample, divide it into 3 parts, take each part to a different pool store for their testing, then compare the numbers. Sure some are better than others, but you never know which one it will be, and if it will be good the next time you go in and a different person is running the test. As to the FC reading of 0 this likely means you have organics in your pool consuming all the chlorine, most commonly this is in the form of algae. To put things simply chlorine kills algae, but it must be maintained at shock level until all of the algae is dead. If the chlorine level is not high enough, then it can't kill the algae faster than the algae reproduces, if not kept high long enough, then a fraction of the algae remains alive and then starts multiplying again out of control as soon as the chlorine level drops drops down and within a few hours your back to square one. This is part of the reason it is so important to have a good test kit, and dose frequently when trying to clear an algae bloom. Once you get your new test kit in we can get a better idea of your real situation, and get you on course to clear things up.
Ike
ps on the issue of bleach and liquid chlorine, as Richard said, they are the same thing, just liquid chlorine is typically more concentrated, when it is 3%, 6% or now 8.25% (the new concentrated bleach that showed up on the market this year) it is typically called bleach, 10% -12% is typically called liquid chlorine (10% bleach though is common in industrial laundry programs like at hotels, etc.), and anything over 12% tend to only be used in industry as it has a very short shelf life.
also it is hard to compare levels being called low or high, as we do not typically agree with pool stores on these terms for the accepted ranges, for some things they may say things are in the normal range, and we may think it is insanely high, and vice versa.