Welcome to TFP! Good to have you here
You need a reliable test kit. Order this as soon as you can:
TFTestkits.net
Sorry to right away say "spend money" but that kit will pay for itself in cheaper and better pool maintenance before the summer is over. That's what TFP is all about. Super clean pools and low cost. We don't go to pool $tores except to buy a couple of rare things or pool toys. We do not take their advice on what to put in the pool. Our biggest job here is fixing the serious problems they cause with their costly magic potions.
While you wait, put 1/2 gallon of chlorinating liquid in it, and then add about 1/4 gallon each day.
Buy 8.25% bleach from WalMart or wherever - not scented, not splashless, not anything that doesn't have a % on it. Or if you see 10% pool chlorine, that's good as well. Buy fresh stuff. It will have a manufacture date like 16180 (16 means 2016 and 180 means the 180th day of the year)
And just one time, add 4 lbs of stabilizer (CYA, cyanuric acid). This is a one-time addition. Don't pour the powder directly in the pool. I have no idea where you live, but I believe Walmart sells this, or it's one of those rare things you might need to buy from a pool $tore. Don't let them talk you into anything else if you go there.
Load the CYA one pound at a time into an old gym sock with no holes in it. Put the sock in a bucket of pool water and squeeze the sock, then pour the water into the pool near where the pump shoots water back into the pool. Repeat this until the sock is empty, fill the sock up again, etc. until it's all in. Might take two evenings to get that all done.
Or you can rig up a stick (fishing rod length) to hang the sock from in the water, but not touching the vinyl side of the pool. Squeeze it now and then to help the powder dissolve. Hang the sock in front of where the pump shoots water into the pool.
Read this:
TFPC for Beginners
And this:
Pool School - ABCs of Pool Water Chemistry
And have fun with the pool! You can swim in it as soon as half the CYA is dissolved. Immediately after adding the 1/2 gallon of chlorinating liquid, it might be a bit strong, but will not be if there's a bit of CYA in there, which absorbs some of the chlorine and holds it in reserve.
Come on back with any and all questions
