Confusion about Alkalinity level

[pro99line]

We bought a house recently that has a 20x40 8ft deep pool with a diving board. I calculated it to be roughly 33000 gallons. I had to repair the aqua rite board by soldering on a new voltage limiter and replaced the pump. Everything is nice and clear but i took my water to the local pool store to test and they only recommend i add 1/4 gallon of muriatic acid based on the test results. They use a centrifuge style computer system for their water testing, not vials and chemicals. I have read the ABCs of water chemistry here on this site and what they say does not match up. Can anyone advise me on these test results.

Salt water pool
33000 gallons
Vinyl liner

Free Chlorine - 7.27 ppm
Total Chlorine - 7.52 ppm
Combined Chlorine - 0.25 ppm
Recommended range by lps 2-4 ppm.
I asked them if I should turn down the salt generator and they said no.

pH - 8.0
Recommended range by lps 7.2-7.8
They want me to add 1/4 gallon muriatic acid.

Hardness - 171 ppm
Recommended range lps 175-350 ppm
The ABCs of water chemistry article state this doesnt matter and can be 0 because I have a vinyl liner.

Alkalinity - 43 ppm
Recommended range lps 80-120 ppm
ABCs of water chemistry shows range of 60-120 ppm and states this being low can cause pH swings but the lps stated not to do anything thats it is fine.

Cyanuric acid - 54 ppm
Recommended range lps 40-100 ppm
ABCs of water chemistry shows range of 70-80 ppm. Should I raise this?

Copper - 0.9 ppm
Recommended range lps 0-0.3 ppm
Pool store told me to do nothing even though the results are high.

Phosphate - 0 ppb
Recommended range lps 0-500 ppb

 

[Mr Bruce]

Welcome to TFP!

We don't put much stock in pool store testing. A TF-100 or a Taylor 2006c is what you need. When you get yours, post a full set of results and we can go from there!

 

[pro99line]

I was just reading the test kit article on here. I had bought an AquaChek 7 yesterday at the pool store. After reading the article and what you said, looks like i will be ordering a new kit from Amazon.

 

[Patrick_B]

Welcome to TFP!

What we find way too often is that those types of results can't be trusted. We base all the advice we give on solids test results, and the best way to get them is having your own Test Kit. I really doubt the TA of 43 with pH 8.0, and wouldn't advise you taking action on those numbers without you verifying them on your own with a reliable kit. I know its not what you want to hear, but not likely a surprise if you've done much reading here. We usually suggest the TF100 first, or the K2006C from Taylor, but the former is a better buy in terms of value to dollar. And the reagents, also Taylor are always much fresher.

Our recommendations for levels also wont match up to industry standards, largely because they don't acknowledge the Free Chlorine and Cya relationship that we strongly adhere too. Others will vary some, but what we do is proven over time to be absolutely effective and successful. There's also plenty of science to back it up as well. Check out Pool School some more, and make sure you get a handle on the ABCs first. Once you get a kit with some fresh numbers, there will be plenty of folks around waiting to help and answer any questions that may arise.

 

[spinPHD]

Agree with what the above posted. If you can, return the strips.

If you can't, you can always keep them around. I still have my strips that I had before finding this site and getting proper test kit. I don't use them to calculate any levels, but if I simply want to know if pool has chlorine in it or not I will. Wouldn't buy them again though, just wanted an excuse to feel like I didn't waste my money.

 

[pro99line]

So money not being the issue, which test kit is better TF100 or Taylor 2006C?

 

[spinPHD]

I have Taylor and love it, so no experience with TF100! I would have done TF100 since it gives you more of what you need and less of what you don't use often. However, as an Amazon prime member I went with Taylor.

If you get Taylor, definitely go with the C version since you get larger regeant bottles. Some of them you won't use often, but saves you on cost of refills of the more used ones

If you get TF100, go with the XL option. No matter what kit you get, I would also get a speedstir. I haven't got one yet, but it's on my wish list. Would have bought it all ready, but needed to save something for my girlfriend to get me for my birthday.

 

[drharris]

I love my TF-100, and it arrived quickly. If your pool is green or having issues you might need the XL option, but otherwise the standard kit will be enough since the reagents need to be replaced each year or so. Highly recommend the SpeedStir addon; it's a good price there, and it makes testing easy/fun.

But either kit will work great for you.

 

[pro99line]

Just ordered a new kit. Will post when i get my results. I did find out the system the pool store uses is a Lamotte waterlink spintouch. Lamotte is what i always used on my salt water aquariums, 15 years, and always had good readings. That is why I trusted their readings but not advise. Hopefully i will get my kit early next week and get some numbers so i can get this figured out. Thanks again.

 

[pro99line]

Got my TF 100 test kit and some other test products from them. These are my readings.

Salt - 3300
Copper - 0
Iron - 0
Borate - 0
PH - 7.5
Total Chlorine - 3.0
Free Chlorine - 2.5
Combined Chlorine - 0.5
Calcium Hardness - 150
Total Alkalinity - 50
CYA - 20. I am not sure how accurate this is yet. I also used the CYA calibration solution which is 50 but I also got a result of 20 with it also.

 

[pooldv]

You need more sunlight for your CYA test. Back to the sun with lots of su light flooding the side of the tube but not into it. Hold the tube at the top so you don't block the light.

Add your pool info to your signature so we can better help you. More here on how and what to add, Pool School - Read This BEFORE You Post

 

[pro99line]

Signature added. Thanks for the advise.

 

[pooldv]

Your TA is probably ok at 50 with an SWG pushing up your pH. If pH gets erratic then you can raise it to 60 with baking soda. But as long as the pH is stable 50 is fine.

 

[pro99line]

After some more reading on here, looks like it is recommended for me to get my TA between 60 and 80, my FC more around 4.5 to 6, and I will retest the CYA.