Bought new house with pool, sequence of fixing the problem

[Xiaosong83]

Hi everyone, looking forward to joining the community.

We just bought a house in Dallas with a 14K gallon pool that is about 5 years old.

Here is the water parameters from my TF test kit today:
FC: 0
pH: above 8.2, guessing around 8.4 or 8.5
TA: 90
CYA: 120 (guestimate as I couldn't see the black dot before I even reached the 100 line)
Calcium hardness: 750
Temp: 70 deg F

The previous owner had a pool company maintain the pool and I tested the water and met with the pool company today. They were recommending adding algaecide once a year and cleaning the pool filter (Jandy CV460 cartidge filter) twice a year. They stated that they usually just put pucks in the pool. Their last service according to the pool company was about 3 weeks ago. When I asked him about how to lower the CYA, he suggested waiting for the rain.

What's the best way to start fixing the pool?
I think based on what I have read, I should start with a 50% drain and fill to lower the CYA first. After that, I should then re-test and then adjust the pH with muriatic acid and then add liquid chlorine, is this correct?

I have a overflow drain in the side of the pool that empties out to a pop-up valve in the street. I also have a 1hp sump pump that I bought for something else in the past. Can I just stick a water hose into the bottom of the pool and exchange the water by let it drain via the overflow drain? Or should I try and use the sump pump on one end to empty the pool and fill it with the water hose on the other end?

Thank you guys for your help!

 

[HermanTX]

Good morning and welcome to TFP.
It may be best to do the CYA test again but use the diluted method.
Take the CYA bottle and fill it half with pool water and the other half with tap water. Tap water has no CYA. Shake it up well, then pour half out such that the remainder is your “diluted pool sample”. Then fill the bottle with the R-0013 Reagent as per the test directions. Shake it well for 30 seconds. Then pour into the CYA tube to read the CYA value. Whatever is your value you need to multiple it x2. So if you now read 60ppm, then your real CYA is 120ppm. It is not perfect but provides a better value then being >100.
This will tell us if you need to drain 50% or more of your pool to lower CYA.

Do you plan to use liquid chlorine (LC) going forward?

Draining will also lower your CH which is on the high side.

Do you have muractic acid to lower pH? Your TA is fairly good so lower pH and continue to monitor TA.

Once we have a better CYA value we can make decisions on other aspects.

Do you have any algae?

 

[TinFoilHat]

Fire the pool company and get 5 ppm of liquid chlorine into that pool STAT!
Pool Care Basics
FC/CYA Levels
PoolMath

 

[Newdude]

get 5 ppm of liquid chlorine into that pool STAT!

Minimum is at least 10 and the 120 CYA might come back even higher with the diluted test. The tab/shock pool I inherited was 360 minus lots of variance from several dilutions. 100+ may look the same on the view tube.

 

[JJ_Tex]

+ 1 on getting chlorine in the pool ASAP. With water temps flirting with 70's and the swim season quickly approaching, algae will love a 0 FC environment.

 

[Xiaosong83]

Thank you guys for the advice.

I will retest the CYA today. I don't have algae right now.

Poolmath recommended around 2 gallons of 10% chlorine. Should I just add that now without adjusting pH first with muriatic acid?

 

[Newdude]

I don't have algae right now.

Algae is microscopic. By the time you can see it, it's exponential growth is a runaway train. This is the downfall of the industry ways. Algae is beat down enough to have clear water again, and a couple weeks later it becomes visible again as a new problem that was never properly addressed.


Testing will show you what you can't see and prove if it has organic growth or not.
Overnight Chlorine Loss Test

Poolmath recommended around 2 gallons of 10% chlorine. Should I just add that now without adjusting pH first with muriatic acid?

Yes. FC is always king. Poolmath tells me that's 7.1 ppm if you're still at 0 (10% / 14k gallons) just to make sure we are seeing the same thing.

 

[Xiaosong83]

Yeah, that is a good point about algae.

Here is what the poolmath app shows me.

 

[JJ_Tex]

You got it. 2 gallons of liquid chlorine will get you into the target range. That will get you by a few days, so if you are running to the store, buy 4+ gallons.

 

[Xiaosong83]

You got it. 2 gallons of liquid chlorine will get you into the target range. That will get you by a few days, so if you are running to the store, buy 4+ gallons.

Good point!

 

[pjt]

TA: 90
Calcium hardness: 750

What's the TA and CH of your fill water? Any idea how the CH got elevated? The drain and refill to lower CYA will also lower CH.

The previous owner had a pool company maintain the pool and I tested the water and met with the pool company today. They were recommending adding algaecide once a year and cleaning the pool filter (Jandy CV460 cartidge filter) twice a year. They stated that they usually just put pucks in the pool.

You've proven to yourself the pool company does a terrible job managing your pool.

Don't add algaecide. It's simply unnecessary if you adhere to TFP methods and have enough FC for a given CYA level. Plus, many of them have copper, which you never want in your water.

The constant use of trichlor pucks drives your CYA to an unmanageable level.

What's the best way to start fixing the pool?

Fire the pool company. You have a superb test kit and can manage the pool much better yourself.

I think based on what I have read, I should start with a 50% drain and fill to lower the CYA first.

Let's first see the results of the diluted CYA test.

then add liquid chlorine

LC and salt water chlorine generator (SWCG) are the only two long term sustainable chlorination methods. I would highly recommend getting a SWCG, especially for our Texas climate. It's by far the cheapest, easiest, and most convenient way to chlorinate your pool.

 

[Xiaosong83]

What's the TA and CH of your fill water? Any idea how the CH got elevated? The drain and refill to lower CYA will also lower CH.

Here is the fill water info:
TA: 90
CH: 150

Let's first see the results of the diluted CYA test.

The CYA test is a bit subjective. I tried diluting it by 2 and go around 160, then tried diluting it by 4 and got in the 120-130 range. I did the standard solution of 50ppm to see what it is supposed to look like so I think my CYA is probably around 130 +/- 10 ppm.

LC and salt water chlorine generator (SWCG) are the only two long term sustainable chlorination methods. I would highly recommend getting a SWCG, especially for our Texas climate. It's by far the cheapest, easiest, and most convenient way to chlorinate your pool.

I added 2 gallons of liquid chlorine yesterday so I am at FC of 7.5 and CC of 1 currently. The pH is still 8.4ish but I haven’t added the muriatic acid yet.


I want to explore the SWG a bit more as then I won’t have to exchange as much water and simplify my maintenance. However, the pool company that came to install the safety fence raised the point that it would affect the coping around my pool, although from what I was reading online, there may already be a good amount of salt in my pool since it is about 5 years old and not sure it’s ever been drained and filled so maybe the worry about damaging the coping is overblown.

For those of you in Texas, is there a company that you like that does the SWG conversion? I have the Jandy system with iAqualink and have a Fusion2 (non-salt) version so if I just bought the salt cell and panel online, could I just insert the salt cell into where the tablet dispenser goes? I guess I would need someone professional to install the panel to have warranty though.

 

[HermanTX]

The CYA test is a bit subjective. I tried diluting it by 2 and go around 160, then tried diluting it by 4 and got in the 120-130 range. I did the standard solution of 50ppm to see what it is supposed to look like so I think my CYA is probably around 130 +/- 10 ppm.

The more the sample is diluted the greater the range of error. So Let’s just say CYA is 130ppm. I would do a 50-60% drain to have a CYA of 50-60ppm . This way you are ideal for using LC and if you go to salt system then it is much easier to add a little CYA then it is to remove it.

do you know why the CH is so high if your tap water is 150ppm? Were you or someone else using cal-hypo as the sanitizer? Or someone tried to increase CH and overshot it.

I think Jandy is only needing a “professional” to install the SWCG. If you have a good understanding as to how to connect it, then hire a “professional” handyman or an electrician to do the hookup. It is really just 3-4 connections.
For the plumbing you would want to remove the inline puck chlorinator and put the SWCG there if sufficient space. A “professional “ plumber can easily do it. I guess what I am saying is that you do not need a pool builder to do it.

 

[pjt]

Any idea how the CH got elevated?

@Xiaosong83 Any ideas?

Here is the fill water info:
TA: 90
CH: 150

That's not terrible, but not great. You may want to consider a way to use softened water for your fill line. Harvest as much rainwater as possible.

I want to explore the SWG a bit more as then I won’t have to exchange as much water and simplify my maintenance.

SWCG will greatly simplify your maintenance. It will save you much time, money, and effort. The only downside is the upfront cost.

the pool company that came to install the safety fence raised the point that it would affect the coping around my pool

That's completely wrong. Poor quality materials will deteriorate regardless of water chemistry. Bad water chemistry will likewise cause problems. The amount of salt needed to operate a SWCG is ~1/10th the salinity of seawater. I can't even taste the salt in my water.

there may already be a good amount of salt in my pool since it is about 5 years old and not sure it’s ever been drained and filled so maybe the worry about damaging the coping is overblown.

That's correct. Test your water with a K-1766 and you might be surprised how much salt is in your water right now. All chlorinated pools have salt in them.

 

[Xiaosong83]

That's not terrible, but not great. You may want to consider a way to use softened water for your fill line. Harvest as much rainwater as possible.

We are probably going to install a whole home water softener in the near future as the water around here is pretty hard.

The more the sample is diluted the greater the range of error. So Let’s just say CYA is 130ppm. I would do a 50-60% drain to have a CYA of 50-60ppm . This way you are ideal for using LC and if you go to salt system then it is much easier to add a little CYA then it is to remove it.

What's the best way to drain and refill my pool? I have a overflow drain to the street so should I just calculate my hose flow rate and stick it in the pool and let the appropriate amount overflow through the drain?

I also have a 1hp suction pump, should I use that to empty the pool while filling it with fresh water from a hose at the same time to not let it get too empty? I assume the pool pump should be off for this whole process, is that correct?

do you know why the CH is so high if your tap water is 150ppm? Were you or someone else using cal-hypo as the sanitizer? Or someone tried to increase CH and overshot it.

I'm not quite sure why it's so high. I think the pool company was using shock but the former owner also said that he had to top up the water every few days. The pool is only 5 feet at its deepest point with a sun shelf and it's hot here in the summer so maybe evaporation over time contributed to it?

I think Jandy is only needing a “professional” to install the SWCG. If you have a good understanding as to how to connect it, then hire a “professional” handyman or an electrician to do the hookup. It is really just 3-4 connections.
For the plumbing you would want to remove the inline puck chlorinator and put the SWCG there if sufficient space. A “professional “ plumber can easily do it. I guess what I am saying is that you do not need a pool builder to do it.

Ok, that is good to know. Thanks

 

[PoolStored]

Use the sump pump.
You can do basic calculation on time. Most residential flow is about 5GPH. Or you can get a 5 gallon pail and time how long it takes to get 5 gallons from your hose. The rest is just math.

Read "no drain water exchange" here:

Draining - Further Reading

www.troublefreepool.com

 

[HermanTX]

I also have a 1hp suction pump, should I use that to empty the pool while filling it with fresh water from a hose at the same time to not let it get too empty? I assume the pool pump should be off for this whole process, is that correct?

It is always recommended to use a sump pump such as the one you have to drain the pool. To lower CH and CYA, it is a proportional calculation. If you drain 50% then those test values should be reduced by about 50%.

I'm not quite sure why it's so high. I think the pool company was using shock but the former owner also said that he had to top up the water every few days. The pool is only 5 feet at its deepest point with a sun shelf and it's hot here in the summer so maybe evaporation over time contributed to it?

OK. CH does not evaporate so it accumulates in the pool over time.

A whole house water softener would help. However, when they come out to provide you a quote, ask if they can determine if your pool fill line is hooked to the main house or separate. I know some homes have their exterior faucets plumbed before they connect to the water softener that then provides softened water to the house.