# Thread: what would average SWG Percentage be set at?

1. ## what would average SWG Percentage be set at?

Living in Massachusetts, we get about 4 months pool usage, in a 22000 gal vinyl pool, what shouls an average T-15 Hayward be set at to keep FC levels around 6-7?
Thanks
Ed

2. ## Re: what would average SWG Percentage be set at?

There is a mathematical calculation to figure out how much chlorine the T15 can produce in a given amount of time...but I try not to make it that complicated for me. I would manually dose the FC up to 6 with liquid bleach.

My pool is 14,000 gallons and I run my pump for 5 hours at 25-30% - CYA is 70-80. Assuming I lose 2-3 FC due to sunlight daily. These are the variables you need to consider. The CYA is important because if it is lower, sunlight will burn more FC - and this does have a significant impact on the run time in conjunction with % that you will need to maintain that FC6-7.

You are really going to have to see what works with your pool based on your water balances. So I recommend a liquid dose to 6, run the pump for whatever you feel keeps your pool clear of debris. If you are comfortable with 5-6 hours, then I would probably set it at 50% and measure at the end of day to see where FC landed. If it lands at 5 (dose back to 6 with liquid) and turn it up 10%. Then see what happens the next day.

If it lands at 7 that first day, I would leave the FC at 7, dial down 10% and see what happens next day - remember you start at 7, so if it ends at 6 the next you need to increase it some, say 5%.

I hope the explanation makes sense

3. ## Re: what would average SWG Percentage be set at?

The "average" setting that we see here is somewhere between 5% and 100%. . Sorry to sound snarky....the settings really are all over the place. I would follow jagger's suggestions above.

4. ## Re: what would average SWG Percentage be set at?

I was going to say between 0 and 100, but Duraleigh's answer is much better because 0 is obviously wrong.

One of our members recently created a SWG run time calculator. Here is the thread, the calculator is in his sig, Formula for SWG / Pump Runtime?

5. ## Re: what would average SWG Percentage be set at?

Mine is set at 100% running 6 hrs/day to generate 2 ppm.

Here's yours per swg calc

6. ## Re: what would average SWG Percentage be set at?

There are many variables and there is no one setting that will guarantee you 6-7 ppm.