Feedback on Pool House Water Test + Recommendations, and Intellichem Calibration

[rwemerson]

I only very recently terminated my maintenance guy and thought I was doing fine on my chemistry because my Intellichem readings were within target. Then one day my pH spiked really high in the Intellichem, so I got out the Taylor kit for a second opinion, and it said:

- The pH was sub 7.0 (pee yellow)
- The chlorine was 1.5 ppm free chlorine. (I'm a stupid noob so didn't test for total and thus combined chlorine)
- The calcium hardness was a bit high at 570 ppm
- Total alkalinity at 30 ppm

Because this is all so new to me, I decided to go the Pool House and have them test the water. They found:

- The pH was 6.4
- The chlorine was 1.2 free and 1.7 total
- Calcium hardness of 546 ppm
- Total alkalinity was 22 (very low)

At the Pool House's recommendation, I spent $141 and purchased:

- 50 lbs of total alkalinity increaser (41 lbs to be applied in 25,000 gal pool in 3rds, each 1/3rd six hours apart)
- 6 lbs of pH increaser (2.75 lbs to be applied)
- 2 lbs of superchlorinators (2 lbs to be applied)

Their analysis printout also suggested stabilizer, scale inhibitor, and optimizer (for water clarity/softness), but the guy didn't push on these hard and I asked which chems were "optional" versus not, he focused me on the 3 bulleted items above.

Questions for the community:

• Was any of what the Pool House sold me totally unnecessary?
• I'm starting my Googling now, but clearly I need to be calibrating my Intellichem. Any suggested reading or notes from experience on this topic is appreciated.

 

[ajw22]

• Was any of what the Pool House sold me totally unnecessary?

Probably the pH increaser.

If you increase your TA to around 70 your pH will also increase depending on what you used to increase your TA...

From TA - Further Reading

The simplest way to raise TA is with baking soda (sodium bicarbonate or sodium hydrogen carbonate). In fact, if you look at the ingredient in the chemical bottle that pool stores sell as “alkalinity increaser”, it is precisely that, baking soda!! And, it is often 2X to 3X the price of the stuff in your grocery store.

Chemicals suggested for raising TA. Their effects are:

• Baking Soda = big TA change, small pH change
• Borax = big pH change, small TA change
• Soda Ash/Washing Soda = big pH change, big TA change. Probably more TA change than you want.

It is often best to make large TA adjustments in a couple of steps, testing the water after each step, as adding large quantities of baking soda can raise the pH a little and you don't want the pH going out of range.

What test kit are you using?

Are you using PoolMath to determine the Effects of Adding chemicals before you add it?

Pool Care Basics Archives

Your one-stop shop for all things TFP to include: ABCs of Water Chemistry, Recommended Chemicals/Levels, Test Kits, Troubleshooting, and much more!

www.troublefreepool.com

 

[pjt]

I spent $141

Return all that stuff. Put that money into a quality test kit instead. That is by far the best money you will spend on your pool. The TF-Pro Salt would be perfect for you.

Swimming Pool Test Kits Compared

What pool test kit should I buy? Why not use test strips? Our recommended test kits will pay for themselves in no time!

www.troublefreepool.com

Obviously stop adding MA. You might need some baking soda from Walmart or the grocery store; 10 lbs would raise your TA by 30. It's important to get your pH into the 7s. Raising the TA will help accomplish that and aeration will speed up the pH rise. Is your water warm enough to operate your SWG?

 

[rwemerson]

The TF-Pro Salt would be perfect for you.

Thank you, I will look into this. I currently have a Taylor K-2005.

Obviously stop adding MA.

I've determined I'm clearly an experiential learner. As I was going to bed last night I started thinking, my Intellichem thinks PH is high 7.6 (while Taylor test and Pool House are saying it's low), so the Intellichem is going to keep adding MA no matter what I put in the pool. Super obvious in retrospect and exactly what you suggested.

Woke up today and priority one was to clean my pH and ORP sensors (for the first time) and the results were quite interesting.

Time from cleaning sensor	pH	ORP
Before	7.68	776
1 min after	5.18	757
70 min after	5.96	762

Now I'm back to focusing on getting TA and pH back in line. When I tested this morning with the Taylor kit it was around 80 (8 drops to turn green to red) - whic is a nice improvement over yesterday's starting point of 20-30.

Is your water warm enough to operate your SWG?

Yes, I'm keeping the pool at 55. The heater spec says 52 minimum and one of the employees of my builder who is also being helpful in my ownership education, recommended 55-60 as he says it help reduce condensation on the heating coil and thus prevent rusting.

Sincere thanks for your reply and comments.

 

[rwemerson]

What test kit are you using?

Taylor K-2005

Are you using PoolMath to determine the Effects of Adding chemicals before you add it?

No, but thank you for the suggestion. I will download and begin using.

Sincere thanks for all your comments about the various methods to impact TA and pH simultaneously. Much appreciated.

 

[pjt]

I currently have a Taylor K-2005.

That kit is missing the critical FAS-DPD test. You can buy a standalone FAS-DPD kit (Taylor K-1515 series). I'd also highly recommend a SmartStir or Speed Stir.

Intellichem is going to keep adding MA

The IntelliChem might be creating more problems than it attempts to solve. You should still test with your Taylor kit either way. Manually adding MA is easy and you would have control over dosing.

Yes, I'm keeping the pool at 55.

Would you have water freezing problems if you didn't heat? If not, consider turning your heat off and using liquid chlorine until the spring. Chlorine demand in the winter is almost nothing.

What's your CYA?

 

[rwemerson]

That kit is missing the critical FAS-DPD test. You can buy a standalone FAS-DPD kit (Taylor K-1515 series). I'd also highly recommend a SmartStir or Speed Stir.

Both are now on my shopping list, thank you.

The IntelliChem might be creating more problems than it attempts to solve. You should still test with your Taylor kit either way. Manually adding MA is easy and you would have control over dosing.

I'm keeping the true helpfulness of the IntelliChem in mind as I continue learning. Now that I've cleaned the probes, I will be evaluating it's readings for pH versus the kit. And yes, I now understand gotta test manually to be sure.

In that vein, the color gradient on the Taylor kit feels a bit "imprecise". Maybe it's just me and granted I've only tested 3-4 times by now, but I find it difficult to differentiate between pH 7.0 and 7.2, similarly 7.4 and 7.6 look pretty similar to me. Will I just get used to the coloring the more I do it?

Would you have water freezing problems if you didn't heat? If not, consider turning your heat off and using liquid chlorine until the spring. Chlorine demand in the winter is almost nothing.

It's possible, but rare. I would likely know in advance as consecutive days with temps < 30 F for any stretch would be in the news. I appreciate you calling this out. As I've been learning about my setup, I read the expected lifespan for a salt cell is about 10,000 hours. That's about 14 months.

There's also parts on the Intellichem that Pentair states should be replaced annually. Assuming I can get my arms around managing this tub of water I bought , I could see not using the Intellichem at all, and no heat/salt in winter.

What's your CYA?

I just did the CYA test for the first time and got NO cloudiness in my test water. The Pool House analysis yesterday had my CYA at 5. Looks like Pool Math recommends 30-60. Something else for my to-do list

I also just ran chlorine tests and both free and total looked exactly the same to me, I'd give both a 1. The Pool House analysis yesterday had my chlorine at 1.7 total and 1.2 free.

Where I'm at now
I think I've got my TA in a good range now and am focusing on getting pH back in range. With the TA coming up, the pH appears much better as well and now just under 7 on both Intellichem and Taylor. After that, I'll tackle CYA.

I sincerely appreciate all help and input.

 

[pjt]

the color gradient on the Taylor kit feels a bit "imprecise"

Use a consistent background. I hold the block up to my monitor and use the white part of the Google homepage to illuminate my sample. To help discern colors better, try holding the block sideways or upside down.

I find it difficult to differentiate between pH 7.0 and 7.2, similarly 7.4 and 7.6 look pretty similar to me

Those small pH differences don't matter. Improve your testing consistency. You'll get better with time and experience.

I read the expected lifespan for a salt cell is about 10,000 hours. That's about 14 months.

That's 10,000 hours of generation. Actual lifespan depends on your pump runtime and your generation %. For example, if you operated your pump continuously and had your SWG at 25%, your cell would generate for 6 hours during a 24 hour period.

I just did the CYA test for the first time and got NO cloudiness in my test water.

You'll need to add some CYA. Use PoolMath for the calculations. You can start on the low side since it's winter in the PNW. Warm your water sample to room temperature (>70° F) before testing CYA.

The Pool House analysis

With the addition of a FAS-DPD test, you have an excellent kit. Use it exclusively and avoid pool store testing.

I also just ran chlorine tests

You need more FC in your water, either via SWG generation or LC.

I think I've got my TA in a good range now and am focusing on getting pH back in range.

Aeration will speed up the pH rise.

 

[ajw22]

In that vein, the color gradient on the Taylor kit feels a bit "imprecise". Maybe it's just me and granted I've only tested 3-4 times by now, but I find it difficult to differentiate between pH 7.0 and 7.2, similarly 7.4 and 7.6 look pretty similar to me. Will I just get used to the coloring the more I do it?

Precision in the pH does not really matter for pool care. Just use the colors to tell if your pH is too low, below 7, or too high, above 8.2. pH anywhere in the 7's is ok. and you can use the colors to tell if the pH is in the low 7's or high 7's. Really does not matter if you call it 7.2 or 7.4, or call it 7.6 or 7.8. Figure out what you do and be consistent.

 

[HermanTX]

In that vein, the color gradient on the Taylor kit feels a bit "imprecise". Maybe it's just me and granted I've only tested 3-4 times by now, but I find it difficult to differentiate between pH 7.0 and 7.2, similarly 7.4 and 7.6 look pretty similar to me. Will I just get used to the coloring the more I do it?

In reality you want to know if it is 7.2 vs 7.8 i.e. low vs high. There are a couple of methods to use to get more precise looking at the color comparator.
First, you can put your finger behind the upper most bar and determine if the one below is a good match. if not, move your finger up one and try again. Focusing on a single bar makes it easier to compare.

Second, does the K-2005 have the reagents for acid demand and base demand? I use the acid demand R-0005 and put a drop in the comparator. It will change the color of the solution and that helps differentiate the colors. Just remember you changed it so if after adding the drop it becomes easy to determine the solution is 7.4 then your real pH is higher such as 7.5 or 7.6. There is also a chart in the Taylor book that comes with the kit that explains what each drop represents in regards to MA.
You would use the base demand if you want to see color become more purple (higher on the scale). I tend to have pH in the 7.6 to 8.0 range so I use the acid demand, i.e. to move down the color comparator.

Hope this helps.

 

[rwemerson]

That's 10,000 hours of generation. Actual lifespan depends on your pump runtime and your generation %. For example, if you operated your pump continuously and had your SWG at 25%, your cell would generate for 6 hours during a 24 hour period.

Thank you for this clarification, noted.

You'll need to add some CYA. Use PoolMath for the calculations. You can start on the low side since it's winter in the PNW. Warm your water sample to room temperature (>70° F) before testing CYA.

The note about the water sample temperature is interesting. I'll do that before I retest.

You need more FC in your water, either via SWG generation or LC.

Is this similar to TA and MA, where I should target the CYA (stabilizer) first?

Aeration will speed up the pH rise.

Does this mean run the pump at high speed, leave the pool uncovered, or both?

As stated before, thank you very much.

 

[rwemerson]

In reality you want to know if it is 7.2 vs 7.8 i.e. low vs high.

I appreciate this comment, thank you.

Second, does the K-2005 have the reagents for acid demand and base demand?

It does and I have been experimenting with how many drops are required to bring it to color and then checking the chart in the back for adjustments based on drop count and pool size. Thanks.

 

[rwemerson]

Precision in the pH does not really matter for pool care. Just use the colors to tell if your pH is too low, below 7, or too high, above 8.2. Figure out what you do and be consistent.

Noted and appreciated.

 

[pjt]

Is this similar to TA and MA, where I should target the CYA (stabilizer) first?

You need both, and they can be increased at the same time. If you're using granules, the CYA takes a little time to dissolve. If your CYA is zero, add enough to increase your CYA to ~40. For a 25k gallon pool, that's ~9 lbs. Use PoolMath --> "Effects of Adding" --> "Dry Stabilizer". When the weather warms up, you'll want to target a CYA of 70-80 with your SWG chlorinated pool.

CYA - Further Reading

www.troublefreepool.com

The Free Chlorine and Cyanuric Acid Relationship

Managing your cyanuric acid and Free Chlorine levels is key to stabilizing your pool. Learn how these two items affect each other.

www.troublefreepool.com

Does this mean run the pump at high speed, leave the pool uncovered, or both?

Aeration - Further Reading

www.troublefreepool.com

 

[rwemerson]

Aeration - Further Reading

www.troublefreepool.com

Just wanted to say thanks for this tip. I've been running my spa air blowers for about 2.5 hours and (per the Intellichem) increased my pH from 7.23 to 7.32. I'll test with the Taylor tomorrow AM as well and see if it's up from this morning.

I also wanted to ask you about something from your first post...

Soda Ash/Washing Soda = big pH change, big TA change. Probably more TA change than you want.

At that time the pool was reading TA 22-30 and pH was ~6.4 - which I believe to be pretty low. I don't have a lot of experience, but what TA/pH levels would warrant use of soda ash?

Lastly, I'm now the proud owner of some pretty big boxes of baking soda and Borax

 

[ajw22]

At that time the pool was reading TA 22-30 and pH was ~6.4 - which I believe to be pretty low. I don't have a lot of experience, but what TA/pH levels would warrant use of soda ash?

When TA is 0.

 

[pjt]

I'm now the proud owner of some pretty big boxes of baking soda and Borax

With a SWG chlorinated pool and stopping excessive MA additions, you will seldom (maybe never) use them. In 13 years of pool ownership, I've never added either to my water.

What's the pH, TA, and CH of your fill water? I'm assuming you get plenty of rain and rarely need to use fill water.

 

[rwemerson]

With a SWG chlorinated pool and stopping excessive MA additions, you will seldom (maybe never) use them.

If I move off SWG to liquid chlorine for winter, would the probability change?

I'm currently talking to my builder (and Googling) and how to check what % my SWG is running at as well as how I can transition between it and the IntelliChem liquid chlorine if desired. I'm not pushing the IntelliChem, but I've got it and can use now through next summer to determine how much I trust it.

What's the pH, TA, and CH of your fill water? I'm assuming you get plenty of rain and rarely need to use fill water.

We average 40"of rainfall a year here, but my backyard is surrounded by a dozen Evergreens and a handful of leaf-droppers I keep the cover on most of the time when not in use (a constant battle with my wife as she likes the aesthetic of the pool as much as it's utility). As such, my auto-fill is likely providing most of the fill water.

To answer your question, my tap water came in at:

• TA: 20 ppm
• pH: 8
• CH: 20

As always, I appreciate your help.

 

[pjt]

If I move off SWG to liquid chlorine for winter, would the probability change?

No. But for trichlor tab users it becomes a consideration since the tabs are very acidic.

check what % my SWG is running

I don't see automation in your signature. Are you operating all your equipment independently? You would be an excellent candidate for IntelliCenter.

https://www.pentair.com/content/dam/extranet/nam/product-related/product-manuals/pool-and-spa-equipment/intellichlor/IntelliChlor_Quick_Start_Guide_and_Tips_English.pdf

 

[rwemerson]

I don't see automation in your signature. Are you operating all your equipment independently? You would be an excellent candidate for IntelliCenter.

Good call out, just updated my signature, I do have IntelliCenter on the pool we've been discussing.

And based on this conversation, I now realize what the IntelliChlor section of the Pentair app is for...SWG %. You can kind of see it in my profile pic, but the pool (20,000 gal) has an integrated hot tub (5,000 gal) and the schedule for heating/chlorinating/etc is:

- Pool: 9am - 5pm (hot tub spillway runs 12pm - 3pm)
- Hot Tub: 5pm to 9pm
- Pool: 9pm - 5am
- Hot Tub: 5am - 9am

So pool for 16 hours a day SWG at 40% and hot tub for 8 hours a day with SWG at 4%. The pool set point is 55 and the hot tub 85. I manually increase the hot tub temp when we decide to use it. My pump is currently running 24x7 at 30 GPM.

I'm currently focused on just understanding chem management and costs, but I plan to try and dial in electrical and gas costs next.

The primary reason we didn't winterize and shutdown the pool and just maintain the hot tub through the winter is my wife really wants the option to heat and use the pool on "special occasions" if desired.

I had originally set my scheduled pool heater temp at 40 for the winter (minimum allowed by IntelliCenter) until I realized that was too low for SWG. As suggest by you, I am looking to understand what it would mean to switch to liquid chlorine for the winter and thus not meaningfully heat the pool.