Back in July I had to replace my pool liner. I posted the steps I went through to replace the liner. I had some great responses to it. So I figured I should document some of the issues I ran into after having to dump 9600 gallons of water, replacing the liner and refilling the pool.
I decided to fill the pool from my garden hose. I could have had water hauled in, but it would cost almost as much as filling it from the spigot. But by filling it from MY hose I can control the rate it is filled.
The water coming out of the spigot is not perfectly balanced for a pool. The pH and alkalinity are within normal ranges for you and me to use daily, but they are not ideal for a pool. When those two things go high or low you will have problems with cloudiness (white, green or yellow depending on chemistry) and maintaining a proper chlorine level. Which can lead to either algae growth or over chlorination. My problem was a white cloudiness. In my case the pH and alkalinity were way too high. First things first … get the chlorine level up. For my above ground pool I have 9600 gallons of water. It tested faintly for chlorine right out of the hose. I dumped in 2 gallons of liquid chlorine. It was just enough to bring the chlorine up to the ideal levels. I didn’t even try to adjust pH or total alkalinity until the water hit 82 degrees. Believe it or not, the pH and TA can be affected by water temp.
OK a bit of a back-track here … I guess I should tell you the testing method I use. I found these really easy to use test strips, you dip them in the water, pull them out and hold them level for 10 seconds and compare the sections to a color chart and you will see if you are high or low on hardness, total chlorine, free chlorine, pH, total alkalinity and cyanuric acid. They are called Aquacheck Select.
As I mentioned earlier pH and alkalinity were high. My pH was sitting around 8.0ish and the alkalinity was around 180ppm. I needed to bring the alkalinity down first into the 80-120ppm. I’ll be honest with you, you cannot control the pH if the alkalinty is out of whack. Enter Muriatic Acid. Use this carefully. And do this slowly. High TA (Total Alkalinity) is not bad, it just makes adjusting pH difficult. I had to bring the TA down to 120ppm from 180ppm. I started with 16oz of muriatic acid. It needs to be added with the pump off. CAREFULLY add the acid and let it settle to the bottom of the pool … you will see the “ripples” as it settles. Wait 60 minutes and turn the pump on for a 6 hour cycle. Check the pool water chemistry when you turn the pump off. You should see a slight drop. But wait another 24 hours and test again. You will see another slight drop. Keep waiting. After 3 days your tests should show the TA as stable. In my case my test strips showed a color somewhere between 180ppm and 120ppm. I added another 8oz. ran the pool filter as normal and waited another 3 days. I hit the 120ppm. With using muriatic acid it also lowers the pH but not all the way. I then added about 2 cups of pH-Down and waited a couple days. I added another cup and waited a couple more days. Bingo! I was between 7.2 and 7.8 and the TA dropped just a little below the 120ppm. All the while I was maintaining a TC (total chlorine) of 3ppm and FC (free chlorine) of 1ppm. As soon as the water hit the 7.2 to 7.8 pH range and the TA dropped down to 120ppm the water cleared up.