Keith - first, good job finding this site and asking questions. Second, glad you followed FPM's advice to drain and re-fill. Third, it will help people get the whole picture and be able to help better if you keep all your posts on a topic or issue in one thread, AND if you add some of your pool specs into your signature.
If you have just refilled the pool and haven't added anything, your CYA will be zero. You won't be able to test it with the test kit you have, but that might be okay for your pool (slightly bigger than mine), especially if you will only have another couple months of swimming (I didn't notice where you live). You will want to target a CYA level of about 40. If you know how to use the pool calculator, plug in a value of 0 for starting CYA and 40 for target. It will tell you how much stabilizer to add. Buy it (some Walmarts have it) -- you want 99% or higher cyanuric acid. Sometimes called CYA, stabilizer, or conditioner. Put the amount listed in the pool calculator into an old athletic sock and hang that in front of the return jet. It may take a day or more to dissolve, but if you massage it it will speed up and in fact could be done in an evening. Once it has dissolved into the pool and had time to circulate, assume you have a CYA of 40. That means you'll want to keep your FC at a minimum 3 and a target of 5. You can use the yellow side of the test-block to check chlorine (ignore the Br label). It will give you total chlorine, not free chlorine, but for your purposes they should be same thing unless you see something funky going on in the pool. You never want it below 3, so the idea is add enough each evening to get it up to 5 (or 6) so by the next evening, even in sun and with swimmers, the FC doesn't drop below 3. If it ever looks "dull" or if you have a lot of swimmers or "incidents" with young kids, bump up the chlorine to stay ahead of any crud getting a foothold.
Ideally you'd test your CYA about a week after adding it, or after tons of rain or lots of loss of water through splashing or otherwise. But if you keep track of all things you put in the pool with CYA in it (ie, don't use pucks, just use bleach), you should know your CYA closely enough to manage the pool without a test kit. That said, if you can swing it, I HIGHLY recommend buying an FAS-DPD chlorine kit and something that tests CYA. Others on the board clearly think an OTO and pH test kit is all that is needed for our small pools. (OTO is the yellow chlorine tester you have). I've said it before, but for me, I work full time and don't have a ton of time available to swim with my kids, so when my schedule, their schedules, and the weather all line up for a good swimming opportunity, I want to KNOW my pool is well-balanced and ready for us -- and I don't feel like I can do that without the more precise chlorine test (FAS-DPD) and I don't know my target FC without knowing my CYA, so for me, I'm not comfortable not testing CYA.
If you don't know how to use the pool calculator to figure out how much stabilizer to add, post back and I'll plug in the numbers -- I guess I'm being lazy right now. Happy Swimming, and don't worry, it really does get easier and soon you'll know what amount of bleach you need to keep it sparkly, and the look of your water will give you signals that will help you get it back in balance even if you don't spring for the better test kit right away.
