Taking over pool duties. CYA 500+

pink

Active member
May 13, 2020
28
Long Beach, CA
Since being quarantined I've had a lot more time at home. We didn't like our pool guy anyway so I've decided to take over the pool duties. I've been learning a lot in the past two months but I'm stuck with high CYA and what to do now.

I've taken the pool water to Leslie's but have since gotten a Taylor kit to test at home. Lelie's says the CYA is at 150 but I've read it can be higher and to do a dilution test. I looked up the dilution test on Taylor's website. 1 part pool water to 1 part tap, multiply by 2. 1 part pool, 2 parts tap multiple by 3. According to the Taylor website when doing a dilution test with 1 part pool water and 3 parts pool water the multiplier is 5 not 4.

So with that in mind I did the dilution with the black dot and the water is cloudy even before reaching the 100 mark. That means 500 ppm!

I've pulled the chlorine float and stopped the tablets. We swam in the pool the other day and chlorine dropped to 0-1. I've increased the chlorine to 4.8ppm with liquid but I've heard it should be even higher to sanitize with high CYA...

The ph is hard to keep down. I have it at 7.8 right now but it seems to keep going up. Have added 2 gallons of muriatic acid over the month.

TA is at 250
Total hardness on the test strips is off the chart darkest color.

My pool guy puts in phosphate killer every week. I've added 4 oz of PR-1000 2 weeks ago, it looks to have kept the phosphates down, I'm not trying to add phosphate killer every week, but this seems to be his way of keeping pools with high CYA in check.

Is it time to drain?? Does everyone in California just have high CYA and not know it? Everyone I talk to has a pool guy and they have never drained their pool. Please help. Thanks.
 
Welcome! :wave:

You might have a record for high CYA. I imagine the only reason your pool hasn't exploded in green algae is the phosphate remover. As an aside, if CYA is north of 200, and you're only keeping "normal" levels of FC in the water, your pool hasn't been sanitary. CYA comes from trichlor pucks and dichlor "shock." It's not present in nature. Doesn't come in tap water.

But a drain and refill is in your future. Good time to do it, with no immediate threats of water restrictions. If your pool is vinyl lined -- very unlikely in CA -- you have to leave at least a foot in the shallow end. If the pool is plaster or fiberglass, there is the risk of floating the pool if the water table is close to the surface. Long Beach is pretty close to sea level. I hope you're well above the water level. A floating pool will break the buried plumbing. Look around the neighborhood for any ponds, lagoon, or groundwater recharge basins with water in them.

Once you replace the water and get it mixed with whatever residual is left, rebalancing can be done in a matter of hours.
 
Thanks Richard,

I am at 23 ft above sea level. I've texted the previous owners if they ever drained the pool. The bottom used to be white and the owner in 2008- 2012 who did a lot of the work drained it to paint it a warm gray color. So it's possible the last drain was 9-10 years ago.

It's a plaster bottom. Temps right now are mild in the mid 70s but sun is hot, do I have to risk the plaster cracking in this weather? What chemicals to use to clean stains?
 
Thanks Richard,

I am at 23 ft above sea level. I've texted the previous owners if they ever drained the pool. The bottom used to be white and the owner in 2008- 2012 who did a lot of the work drained it to paint it a warm gray color. So it's possible the last drain was 9-10 years ago.

It's a plaster bottom. Temps right now are mild in the mid 70s but sun is hot, do I have to risk the plaster cracking in this weather? What chemicals to use to clean stains?
I've never drained mine all the way, so no firsthand advice on stains or cracking.

FWIW, my inlaws' pool was left sitting empty for years and my brother in law got it going again when he moved in without any problem. No cracks.
 
You can also do a no-drain water exchange, but with that high level of CYA you might end up going through a ton of water. Still if you’re worried about the plaster or the water table, it might be the safest option. There’s also reverse osmosis but I don’t know if that’s available or affordable in your area.
 
I We swam in the pool the other day and chlorine dropped to 0-1. I've increased the chlorine to 4.8ppm with liquid but I've heard it should be even higher to sanitize with high CYA...

The ph is hard to keep down. I have it at 7.8 right now but it seems to keep going up. Have added 2 gallons of muriatic acid over the month.

TA is at 250
Total hardness on the test strips is off the chart darkest color.
Yes, FC should be maintained at 7.5% of CYA, so if your CYA is really 500 you need your chlorine at 37.5. Now, it is doubtful you are at 500, but we have no idea where. Each level of dilution increases the internal error of the test exponentially, so all we can really say is that you CYA is way high.

If you have a test kit, why the test strips for CH?

So, three choices:

- Full drain and refill

- A no drain refill where you use a large tarp to try ot separate old water going out and new water coming in. You will still use a lot of water.

- Reverse Osmosis This is a system of running the pool water thru a membrane filter which takes almost everything out of the water. There is some water loss, can take more than 24 hours and costs in the $1,000 range. A quick google search showed that thre appears to be some folks who do this in LA County.

Most go with the drain and refill. Before you start, work out a few things to make sure it's as quick as possible.

- Where will the drain water go? Sewer, storm sewer, somewhere on your property? A flood of water running down the street will have City/County folks looking at what you are doing. Some have ordinances as to how you have to do it.

- Where will you get teh "new" water from? A hose? It can take days to fill a pool with a hose. There are water services that bring a tanker of water, say 10,000 gallons and fill it all at once, for a fee. Some volunteer fire departments even do this as a service with their tanker for a "donation" to their department.
 
pink - I just drained and refilled mine last week. Pool company sent out a huge pump to drain it because they felt bad for their incompetence in letting the CYA get so high. They were pumping it out into my 1/2 acre backyard and the neighbors behind me called to ask if we had a broken pipe. In order not to make enemies of my neighbors behind me, I borrowed a submersible pump that drains through a garden house and fed that into my sewer clean out. The pool company guy came back after I told him I could not use the mega pump and he turned off the skimmers directed all suction toward floor drain, then hooked up another garden hose to the actual built in pool pump and we had that one draining into the grass. Took about 24 hours to drain 85-90% of the water (20,000 gallon pool). My CYA was 180 with Taylor test and diluting 1/2 with tap water. Pool store said 153. Took about 24 hours to refill with 2 garden hoses and the pool filler going. After refilling, Taylor test said CYA was 40 and pool store said 43. I was pleased with my guestimation on how much to drain. Good luck. Pool company is getting fired here too!
 
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For CYA levels at or above 100 ppm, do a dilution to obtain a more accurate reading.

In a container, mix one part sample water with one part CYA-free water (tap or bottled water will do).

Retest and multiply the result by 2.

If the result is still too high, do another dilution, this time using one part sample water to two parts CYA-free water, and multiply the result by 3.

For a 1:4 dilution, the multiplier is 5.


They are accurate in this page.
 
Thanks everyone for your help. If 1:4 dilution-multiplier 5 means 1 part pool water and 4 parts tap then i did 1 part pool and 3 parts pool so multiplier would be 4. Either way I’m around 400.

I think I will drain and refill this weekend. I will report back with new numbers.
 
I think I will drain and refill this weekend. I will report back with new numbers.
- Where will the drain water go? Sewer, storm sewer, somewhere on your property? A flood of water running down the street will have City/County folks looking at what you are doing. Some have ordinances as to how you have to do it.
In CA, this is apparently state law. It's not easy to track down, but I found this:
It is against the law to drain pool, spa or backwash water to a storm drain. Dischargers could be fined up to $25,000 per violation, per California Fish & Game Code Section 5650.

Street drainage and storm drains lead into streams, rivers, and other drainage waterways. Chlorine, bromine, algicides, biocides, water conditioners, stabilizers and other chemicals in the pool water are toxic to fish and other aquatic life. Diatomaceous earth (DE), cellulose fiber and sand particles from backwash water can fill in the spaces in the streambed gravel, preventing oxygen from reaching fish eggs and young fish. DE and cellulose fiber can also clog fish gills.
It took me weeks to find my sewer cleanout when I had to drain for replastering. I finally contacted my local wastewater facility and they were able to send me a diagram of my house showing where the cleanout was, well hidden behind a bush next to the house, requiring some thorny crawling to access.
 
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I think you made the right choice. You will get the added benefit of getting your CH in range as well. Be sure to test your tap water for pH, TA, and CH so you know what you are working with.

I was in your exact boat 3 years ago. After replacing a wall fitting for my Polaris sweeper, I decided to get my own quality test kit. After running all the tests with my Taylor K2006C kit, I discovered I had CYA over 200, CH over 1000, and TA near 200. I fired the pool guy next week and never looked back.

I did a full drain and also acid washed my pool to freshen up the plaster before refilling with fresh water. After the refill, my CH was 350 (tap water CH) and I added enough CYA to get it to 50.

Once you get it to where you where you want, don't add anything to the pool that has any stabilizer (CYA) in it like shock, tablets, or dichlor. Stick with only liquid chlorine. That way you can stick to a certain FC level instead of fighting a moving scale because of the constant additions of CYA.

Pool maintenance will be a breeze. You probably won't need to buy anything other than liquid chlorine and muriatic acid.
 
In CA, this is apparently state law. It's not easy to track down, but I found this:

It took me weeks to find my sewer cleanout when I had to drain for replastering. I finally contacted my local wastewater facility and they were able to send me a diagram of my house showing where the cleanout was, well hidden behind a bush next to the house, requiring some thorny crawling to access.

Thanks for posting that. I doubled checked Long Beach's requirements for drainage. It mentioned periodic draining to the storm drain if the pool water is dechlorinated as ok. They don't mention a fine but require a full drain to a sewer which we are doing.
I think you made the right choice. You will get the added benefit of getting your CH in range as well. Be sure to test your tap water for pH, TA, and CH so you know what you are working with.

I was in your exact boat 3 years ago. After replacing a wall fitting for my Polaris sweeper, I decided to get my own quality test kit. After running all the tests with my Taylor K2006C kit, I discovered I had CYA over 200, CH over 1000, and TA near 200. I fired the pool guy next week and never looked back.

I did a full drain and also acid washed my pool to freshen up the plaster before refilling with fresh water. After the refill, my CH was 350 (tap water CH) and I added enough CYA to get it to 50.

Once you get it to where you where you want, don't add anything to the pool that has any stabilizer (CYA) in it like shock, tablets, or dichlor. Stick with only liquid chlorine. That way you can stick to a certain FC level instead of fighting a moving scale because of the constant additions of CYA.

Pool maintenance will be a breeze. You probably won't need to buy anything other than liquid chlorine and muriatic acid.

Thanks for the vote of confidence!
 
So I'm in the process of draining and refilling my pool. I decided to test the fill water coming from the spigot next to the pool. I was surprised it was so alkaline. It looks like this is common. Here are my results. I first did an Aquacheck 7 and then followed up with the Taylor Test kit.

CH - 120
ph - 8.0+ (reading for my test only shows 8.0 but color was more red than could be matched on chart. Aquacheck was closer to 8.2.)
FC - 0.6
CC - 2.2
TA - 170
CYA - 0 (According to test which stops at 30)

Since my ph and TA are high, will I always be adding muriatic acid as I fill the pool? We lose water here in CA weekly. The hose runs for about an hour each week to top it off.

Are these common numbers for chlorine?

The aquacheck strips showed a color close to 30ppm for CYA that is why I Tested the CYA with the Taylor kit.
 
After you're full, you'll be adding MA to bring the pH down to probably around 7.6 or so. Then you watch the pH - as it drifts upward, you add more MA when you hit 8.0. Over time TA will come down. Then as you top the pool off, your TA will go back up. The only other option is to force TA down through acid addition down to 7.0 or so, aerating the pool back up to 8.0, then more acid and repeat. Not really worth it in my opinion unless you need the TA lower due to other reasons (like a high CSI).

I know municipalities add chlorine to keep water sanitary - does your tap water have the strong chlorine "swimming pool" smell? If CCs are 2.2, I would think you could smell it....

Fill water will have 0 CYA, so when you fill, first thing to do is to start adding CYA with the sock method. Then adjust your pH down, then get your FC up to where it would be for your CYA addition. I recommend starting with enough to get you to 30, waiting 24 hours after it's all dissolved from the sock to test CYA again, and then deciding if you want to go up to 40 or 50 (might be reasonable if your pool gets full sun every day).
 

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