I'm a new pool owner, now I only have a cheap 2-ways tester, which can only test TC and PH.
I just add all the water in to the pool few days ago and set the SWG timer to run for 9 hours a day (3 hours on and 5 hours off).
Today I just made the first test. The test result is 8.2 PH and 3.0 TC. I try to correct this by adding HCl (Hydrochloric acid) and re-program my SWG timer (from 9 hrs/day to 6 hrs/day). I will test it again tomorrow.
The pool shop, who sell me all the equipment, said I don't need to add anything other than HCl to lower PH.
I think I will going out to buy a better test kit, but I'm not so sure about the HCl, Is it ok to use?
My pool is outdoor and subject to direct sunlight about 8 hours a day.