Retest time on chemicals

[TX Pool]

Is there a rule of thumb on how long after you add liquid chlorine you can retest the water?

TBH I was just more wanting to see if I had the volume of my pool correct in the pool math calculator. I tested FC tonight, added some, and tested 30 min later but I got wildly different results in two different spots in the pool. I think I must have tested a hot spot where some of the chemicals collected in a corner before mixing well in the pool.

Is there better way to check the volume of the pool? I did some rough measurements and volume calculations but not sure how close I am to actual. I run a SWG so not overly concerned on adding chemicals but definitely do not want to over add acid as I adjust pH during the season.

 

[ajw22]

Was your pump running on high speed for the 30 minutes?

Usually 30 minutes is adequate to mix chlorine. But some pools have poor circulation so you need to learn what works for your pool.

 

[PoolStored]

definitely do not want to over add acid as I adjust pH during the season.

Adjust pH in smaller increments until you get the volume right.
Also helps to always test from the same location...

 

[ajw22]

Is there better way to check the volume of the pool? I did some rough measurements and volume calculations but not sure how close I am to actual. I run a SWG so not overly concerned on adding chemicals but definitely do not want to over add acid as I adjust pH during the season.

Estimating Pool Water Gallons​

If you need to get an estimate of the amount of water in your pool you can use the calculator at the bottom of the old Pool math web page. You simply enter the pool dimensions and average depth and it gives you the gallons of water in the pool.

Pentair has a Pool Volume Calculator that lets you select from rectangular, oblong, round, and triangle shapes.

There is also a Chemical Way of Calculating Pool Volume using an alkalinity test kit, sodium bicarbonate or acid, and the formula.

Irregular Pool Shape Area Calculator​

Area of Polygon by Drawing is a neat website for plotting all those Freeform pools. The default shape on the graph is a pentagon but you can add points by pressing the up arrow and I got bored pressing it well after making a 100+ sided shape. If you zoom out on the graph you can make your Freeform pool shape with just a few measurements and round off all the extra points.

The area is shown up top at all times and multiply it by the average depth for cubic feet. Multiply that by 7.481 gallons per cf and it should be pretty accurate.

 

[Newdude]

definitely do not want to over add acid as I adjust pH during the season.

You'll dial it in as you go, and it takes some time. If one parameter over/undershoots, they all will. FC isn't the best indicator because bleach loses strength so it's not always going to do what it's supposed to do.