Have ordered the K-2006 and it will arrive 7/25-7/30. Tabs are 99.9% tabs so what do I get for stabilizer and where do I get it? FC....I'm assuming (since I'm new to all this) that that is Free Chlorine and have no idea what the CYA levels are so I don't know if you're telling me Yes, it's safe for swimming or No, it's not. I'm sorry I haven't learned all the lingo yet. I've been reading as many previous posts as possible to learn as fast as I can. Please bear with me. I will have Muriatic acid by this evening and need to know how much to add for a 20' round x 48" deep vinyl pool, to lower the ph. Water is still crystal clear and very inviting and I can't wait (since temps are in the 100s today) to get in there.