Testing Advice

Jul 28, 2015
16
Belton, TX
Thanks to this forum, my pool and spa are looking splendid, and after learning about testing and what levels to watch I need some advice.

Since I have two separate bodies of water, I don't want to spend 30 minutes testing everything three days a week during the summer. So I've only been testing FC, CC, and PH; I use bleach and Muriatic Acid for adjustments . I've tested CH and it's within range and since I'm not adding any more calcium to the water, it shouldn't move. I've tested the CYA and although it's high (I make sure my FC is within a higher range), I know it's not going to move since I'm not adding any more to the water.

So when I test my three levels I adjust the chlorine with bleach as needed, and if my PH is too high I then check my Alkalinity. If my alkalinity is good then I don't worry about PH because i know the Alkalinity will bring it into range, but if it's high I adjust with Muriatic Acid and aerate.

This method seems to be working great and it makes sense to me with my understanding of how the chemicals work with each other, but I'm new to pool ownership and would like any advice from the more experienced members on whether I'm missing something or not.

Thank you for your help!
 
You have a good grasp of everything! Have you tested your fill water yet? You might want to do that just to be sure there isn't a hidden source for CH or other stuff. Some folks have really high pH house water and other unfriendly stuff to contend with. As we say around here. Once you test, then you know.
 
CH will rise over time due to evaporation and refill as almost all sources of fill water have some CH (just about everything but rain water). The exact amount of CH in your fill water will vary though, on the low end from about 50 ppm CH to over 500 ppm on the high end depending on where you live. It can also vary some season to season.
 
You are on the right track. FC, CC, and PH should be checked once a week minimum, and always after a lot of swimming or rain fall. The rest can be checked "every now and then", IMO.

When things seem out of balance like maybe you find yourself adding more acid than normal or needing more chlorine than normal, then check the rest of the numbers then.

But above all, you need to get a feel for what level of attention your pool needs due to water input, rain, debris, usage, and general environment.
 
Welcome to the forum!

If you are manually chlorinating your pool you should check/add FC every day. Doing so will get you familiar with your pool's chlorine demand which in turn can help signal that there is a problem long before the Green Monster.

I understand that with a SWG pool the chlorine levels can be held much steadier, but I would still check FC a minimum of every 2nd-3rd day. I would be very uncomfortable going a week without testing FC and don't recommend it.

I check CC every time I check FC.

pH is important, so I started by checking every time I checked FC (daily) until I had an understanding of my pH/TA balance and was comfortable that my pH was stable. I currently check pH every 2-4 days. Once my pH/TA is stable I check TA monthly.

CYA, while extremely important, tends to stay where you put it LOL. It does not evaporate or dissipate, and takes a very long time to be oxidized by chlorine. I check mine monthly, or anytime there is significant water exchange. Same goes for CH.

As mentioned, check your fill water too... You could have high CH or TA, and if you are on a well, metals will be a concern.

Dom
 
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Great, thanks for the head's up on the fill water; that is something I did not consider but will now!

I was checking the water every day when we first moved into this house and I have a pretty solid feel on how my water is going to be on each test, so now I only test three times a week .... but with the fall approaching I'm seeing that I will soon be able to move to twice a week and then probably once a week during the winter if not less. Not sure if I'm going to close the pool or not this season.

Thanks again for the advice.
 
and if my PH is too high I then check my Alkalinity. If my alkalinity is good then I don't worry about PH because i know the Alkalinity will bring it into range, but if it's high I adjust with Muriatic Acid and aerate.
Almost but not quite.

pH is the parameter that has to be controlled first.....keep it ALWAYS in the 7's.

Let the TA fall where it will. It may not require any adjustment at all and the range is broad. If it's extraordinarily Low (less than say 60) or too high (say 150+) then you might want to consider changing it but the pH will always be your most important factor.
 
Thanks, Dave. The highest I've ever gotten my PH is 7.8 and I've only reduced it when it exhibits an rising trend to which my understanding indicates too high TA.

For example, my spa was showing a rising PH so I tested TA, saw that it was high, and reduced both with the acid. However, my pool has been showing 7.8 for over a week now and I haven't touched the PH because my TA is at 100.

Am I addressing that correctly?
 
Am I addressing that correctly?
Pretty much. i like to think of it like this.....

pH up - 20 mule team borax

pH down - Muriatic acid

TA up - Baking soda

TA down - aeration and acid...it's a process found in Pool School that you must read to make TA change quickly and permanently

Essentially, is the same thing but It stays clearer in my mind to remember it this way.
 
Great ... sounds like we're on the same page. Thanks for the forum; in one month I was able to gain more knowledge than a neighbor of mine who's owned a pool for over a decade. He was shocked when I told him some of the tricks for balancing the water with a reduced cost.
 

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