The pool store guy is wrong. Trust me on this. Go to the top of this page. Read "Pool School" three or four times. Also the "Getting Started" section. Then go to "Pool Chemistry" and read "test kits compared". Taylor or TF, your choice, but the TF100 XL with speed stir is the best option. It WILL seem daunting at first, but it really isn't. Just read carefully and get your kit. A Taylor K100 from a hardware store will get you started with chlorine and ph until the real kit gets there and will continue to be useful afterward ( I test my pool every morning with the K100 and use my TF100 once a week, but my pool is stable.) Chlorinating Liquid is available at decent hardware stores or a big box store as well as Wally World (where in Charlotte do you live?) Muriatic acid is also available there. DO NOT start putting $tuff into your pool because a pool store guy tells you to. Until you do a real test with a real test kit YOURSELF you do not know what your water is like. You can get all the information you need here and without spending a ton of cash.