Clear Blue Water but still new algae everyday

bjsbuds

LifeTime Supporter
Mar 16, 2012
127
Cincinnati, OH
Our pool is several years old, and we have never fought algae like we are this year. We even opened the pool a month earlier than normal. Pool pump has been running for a month now 24/7. Pool was green upon opening. Have a Pentair Cartridge Filter and SWG. Went to local pool store and was sold $150 in chemicals; case of shock, stablizier, algecide, etc. That turned the pool from green to blue cloudy. Swept the pool floor with the Dolphin M4 Supreme several times and cleaned the filters every time.

After two weeks of this, we went to the local Leslie's store to have the water tested. Manager told me there must be something wrong with the SWG because chlorine is registering 0. Called the company that sold and installed the SWG two years ago, and opened the pool. They said nothing was wrong with the SWG other than the weather was too cold to be generating chlorine. They said dump another case of shock in the pool, and no need to buy anything else.

Algae on the bottom of the pool is lessening, but still there, and more forms everyday after cleaning the bottom. This weekend, I decided I would once and for all get this pool in shape. I bought two more cases of shock, a vacuum and hose. I first vacuummed the bottom of the pool, then I took apart the filter and cleaned the cartridges real good. Put them back in and fired up the filter again. Added a case of shock in the evening.

The following morning, pool was still clear, but there was newly formed algae (brown/grey looking) on the bottom of the pool floor. Chlorine up to 4.2, Ph 7.4, TA 120, CYA at 40. I got in the pool and felt the walls, they felt like sand. I brushed the walls three times until the walls were smooth. Added another case of shock.

I was sure I finally killed it all. So when I went down to the pool this morning I was so disappointed to see that brown/grey algae on the floor, and more than the day earlier. I took readings, now Chlorine is up to 10.4, Ph up to 8.0, TA 110. That's all i had time to measure.

What the heck do I do now?

Thanks!
 

BattleOfYakima

TFP Guide
Apr 15, 2016
1,683
Central Florida
Hello and thank you for being a TFP Lifetime Supporter! We are totally here to help you get this pool Trouble Free and running smoothly for the rest of the season!

To do this - we need your help - Since the TFP approach disagrees with the Pool Store Cycle of Pain that you've been on - you need to pick us or them going forward. I assume because you posted this, we won, but I need to make sure you understand that lots of the chemicals they sell, like green/yellow out for example - have chemicals that interfere with our practices and would just end up costing you a lot more! We want you to spend as little as possible, so that's why I want to be honest - you can't go mix their "Advice" with ours.

I'm going to assume you're with us on this, so here we go!!!

1) What test kit do you have and are the chemicals more than a year old? have they been stored outdoors? I ask because we need to make sure we have test results we can trust and aren't wasting any effort because of expired or dead test chems.

2) What we're going to do is called the SLAM. It is a calculated approach to chlorine/bleach additions to ensure you actually sanitize the pool, not just knock the algae down (which you clearly see doesn't last).

3) Have you ever used PoolMath before? Just want to know how much explaining to do along the way.
 

bjsbuds

LifeTime Supporter
Mar 16, 2012
127
Cincinnati, OH
Hello and thank you for being a TFP Lifetime Supporter! We are totally here to help you get this pool Trouble Free and running smoothly for the rest of the season!

To do this - we need your help - Since the TFP approach disagrees with the Pool Store Cycle of Pain that you've been on - you need to pick us or them going forward. I assume because you posted this, we won, but I need to make sure you understand that lots of the chemicals they sell, like green/yellow out for example - have chemicals that interfere with our practices and would just end up costing you a lot more! We want you to spend as little as possible, so that's why I want to be honest - you can't go mix their "Advice" with ours.

I'm going to assume you're with us on this, so here we go!!! YES, YOU WON

1) What test kit do you have and are the chemicals more than a year old? have they been stored outdoors? I ask because we need to make sure we have test results we can trust and aren't wasting any effort because of expired or dead test chems. I have two test kits; TF-100, but it chemicals are tow years old and I bought a Taylor K-2006 last year, but while I have been testing, I just saw that the bottles expire 04/2017. (Ugh, they were expired when I got the kit.) When I noticed that this weekend, I ordered another kit and the salt water test kit.

2) What we're going to do is called the SLAM. It is a calculated approach to chlorine/bleach additions to ensure you actually sanitize the pool, not just knock the algae down (which you clearly see doesn't last).

3) Have you ever used PoolMath before? Just want to know how much explaining to do along the way.
Yes, I have actually been using the Pool Math calculator when I take my measurement down by the pool with my laptop. I have never totally grasped it, but am getting better, after watching a You Tube video.

Look forward to your advice.
 

BattleOfYakima

TFP Guide
Apr 15, 2016
1,683
Central Florida
Fantastic start! Ask any questions you have about it, and I will answer. I can also post screenshots with things highlighted if you don't understand what I'm saying. No offense taken - just be honest so we get you where you need to go - I'm here to help.

So as long as you are using an approved test kit - with FAS-DPD FC CC test... are you? here's what we'll do:

Turn off SWG. Don't add any chlorine or bleach or shock right now. Let FC fall under 10 and then redo PH test. Post result. Before we begin the SLAM we need to ensure the PH is within the range at which chlorine is an effective sanitizer. It should be under 10 tonight or tomorrow.

Once we have your PH good to go, we'll start the SLAM. For your CYA of 40, according to the [FC/CYA][/FC/CYA] chart, your shocking FC level is 16, which means we need to use PoolMath to estimate how much bleach or chlorine you'll need to raise it from let's say 9 to 16, given you 18k gallons. It says 1.5 jugs of 8.25% bleach. If you're using pool store 10% or 12.5% trade bleach/liquid shock or 6% bleach it will be different, just let me know. I suggest buying at 4-6 jugs as we don't know how many we'll need, and it isn't fun to have to go back to the store, and you can use any extra over time.

Once we get your FC to 16, we need to keep testing and bringing it back up to 16 until you meet the three criteria to end the SLAM. Some SLAMS last hours, most last days, and swamps last weeks. Depending on what the pool store sold you - like if they had you add bromine chemicals like yellowout/green out - then this will be longer than it would have, but we'll get you through it.

Just a few additions:
1) FC can go to zero even with SWG at max if there is enough algae or if they had you add bromine sanitizers (as most pool stores love doing - it isn't their pool, right?)
2) we will turn swg on again, just not right now
3) great job on the vac and brushing - it will help a lot!!!
4) pool store liquid chlorine shock is just stronger regular bleach - if you buy regular bleach, which can be cheaper sometimes, just make sure you get the regular concentrated stuff, not ez pour or scented or technology stuff.

Questions? Thoughts?
 

bjsbuds

LifeTime Supporter
Mar 16, 2012
127
Cincinnati, OH
How do you turn off the SWG? My pump and SWG are both connected to same timer. I tried to find the answer on Google & You Tube, but no luck.
 

bjsbuds

LifeTime Supporter
Mar 16, 2012
127
Cincinnati, OH
Just tested again, from over 10 FC this morning to zero tonight.

FC - 0
Ph - 7.4
TA - 110
CH - 220
CYA - 110 (not sure where the 40 reading came from earlier, must have been wrong)

Here is my Pool Math chart:
Screen Shot 2018-05-14 at 8.15.36 PM.jpg
 

bjsbuds

LifeTime Supporter
Mar 16, 2012
127
Cincinnati, OH
OMG, I finally figured out what I have been doing wrong with the Pool Math calculator. After reading the sticky on how to clear a pool with algae, I realize that I have not been entering the 'target' amounts in that column. That is why I never got results with what I needed. I know, DAH. So, now here we go. Please help me go from here.

Screen Shot 2018-05-14 at 9.08.24 PM.jpg

It is so frustrating to know I have spent all this money and it is still not solved.
 

skoum

Well-known member
May 25, 2017
48
TX
Hi there

If your CYA is that high, it will prevent your FC from being effective and will make it drop to 0 very fast. This plus any other living stuff in your pool.

The only way to decrease the CYA level (to 50/70) is to partially drain your pool and refill. Use Pool math to see how much you should drain.

Once you reach 50/70 and have your PH in the 7.2/7.4 range, you can start the SLAM.
 

BattleOfYakima

TFP Guide
Apr 15, 2016
1,683
Central Florida
I'm back! Busy evening, thanks for understanding!

Congratulations on PoolMath breakthrough! Yes, the target field is essential!

So the CYA test is indeed a tricky one, but a trustworthy CYA reading is required before we set our path so we don't waste time and money.

Please double check you followed all the procedures for the test here, and double check this picture clarifying the endpoint.

Super important are the full daylight at your back and glancing down as opposed to staring.

You can pour it back and forth as many times as you need to be sure. I like to pour it in by increments of 5 or 10, glancing down after looking away. Always round up to next highest 10 if between.

If you again get a CYA over 90, please follow step #8 and report the results.


Also - do you have any of the receipts or bottles of the pool store magic potions? Any of the names would help us to make sure we give you the best advice.
 

bjsbuds

LifeTime Supporter
Mar 16, 2012
127
Cincinnati, OH
Well time flies, I apologize for questioning the Taylor K-2006 kit's expired bottles. I purchased the kit back in 2015 from VMinnovations, via Amazon, so it shouldn't be unexpected to have a 2017 expiration date. I am really looking forward to my new kit arriving. Here's is what I ordered: Screen Shot 2018-05-15 at 6.26.56 AM.jpg

When I checked the CYA, I was standing under the gazebo by the deck. It's cloudy today, but I will test it a few more times this morning and report back.

I have attached the Pool Math from last night. Hopefully, this is legible. Screen Shot 2018-05-15 at 6.30.21 AM.jpg
 

bjsbuds

LifeTime Supporter
Mar 16, 2012
127
Cincinnati, OH
Just tested the pool this morning. Readings:
FC - 0 (I can't begin to tell you how much 0871 I put in and never could get it to turn pink)
Ph - 7.4
TA - 110
CH - 220
CYA - 120 - 150 (tested three times with sun at my back, holding tube waist high)
 

mitchellb

Well-known member
Nov 22, 2017
71
Clearwater, florida
Just tested the pool this morning.

CYA - 120 - 150 (tested three times with sun at my back, holding tube waist high)
That's a big part of your problem. How did your CYA get so high? Are you using Chlorine pucks? You will likely need to drain and refill at least half of your pool water to get your CYA down to manageable levels.
 

Demegrad9

Well-known member
May 27, 2017
341
Coventry, CT
The test water will turn pink as soon as you add the R-0870 powder if chlorine is present. Don't waste your R-0871 trying to get it to turn pink, The R-0871 is the reagent that turns it from pink to clear.
 

funandsun

Bronze Supporter
Jun 11, 2017
764
Bloomington Indiana
Big part or Whole part. goodness. Pucks = problems when they are the main diet to any pool


That's a big part of your problem. How did your CYA get so high? Are you using Chlorine pucks? You will likely need to drain and refill at least half of your pool water to get your CYA down to manageable levels.
 

bjsbuds

LifeTime Supporter
Mar 16, 2012
127
Cincinnati, OH
Sorry, I was adding R-870, just typed it in wrong. No, I do not use chlorine pucks. I have only used shock (10%) and my SWG is running (I think, at least all the lights are on). I just kept adding cases of shock, as I thought that was the only way to get the FC to read. Following funandsun's tag line "Rule #1: Chlorine kills Algae and your Filter cleans the water."
 

funandsun

Bronze Supporter
Jun 11, 2017
764
Bloomington Indiana
Sorry, I was adding R-870, just typed it in wrong. No, I do not use chlorine pucks. I have only used shock (10%) and my SWG is running (I think, at least all the lights are on). I just kept adding cases of shock, as I thought that was the only way to get the FC to read. Following funandsun's tag line "Rule #1: Chlorine kills Algae and your Filter cleans the water."

Your CYA levels right now is what is hurting you. Refer to this chart https://www.troublefreepool.com/content/128-chlorine-cya-chart-slam-shock

This is the building block of any successful battle with beating algae and keeping it away.

And thank you for pointing that out.. I will adjust my tagline to better reflect the importance of the CYA relationship in my statement.

Edited
I made that adjustment to my signature.
 

bjsbuds

LifeTime Supporter
Mar 16, 2012
127
Cincinnati, OH
Okay, it looks like I am really going to have to drain part of my pool water, and start over. Then, of course, I will have to replenish all the salt for the pool.

Since I don't have a backwash port, I guess I have to get a sump pump to get water out of the pool.

I really appreciate everyone's help.
 

BattleOfYakima

TFP Guide
Apr 15, 2016
1,683
Central Florida
Thank you for performing the CYA test again and ordering fresh test kit. Just to clarify, this CYA reading was performed with the new or old kit? Yes, the K-2006 is a great kit, AS LONG AS when you get it, you check ALL the expiration dates on the bottles (they are usually different) and make sure they are acceptably far into the future. Generally speaking, you want a date about a year out, but since it is May, if you get anything after 2/19 I'd consider it good enough. Anything sooner, up to you if you want a refund. If they have a date before you stop swimming this season - I mean - that's just horrible, but it happens all the time from online vendors, so check the dates please.

As for the high CYA situation - assuming the testing chems are valid - you have some options:
1. Live with it for now and SLAM anyway (not something we really suggest for many reasons, but technically doable if you want)
2. Calculate and plan draining and replacing water targeting final CYA 70-80.

If the CYA chems are of questionable freshness, I would wait to drain and verify with new kit. In the meantime, if you want to try to keep the water blue - I suggest you target FC 15-20 if there is no visable algae, and FC 30-40 if there is algae, and if it is turning green, FC 40. I'll take a slightly wild guess and say that anytime your FC goes under 12 you're losing ground to algae and the clock is counting down to an algae bloom. Given your likely high CYA, this is 100% why you've had the back and forth battle. Congratulations on solving the riddle - and shame on the Pool Store for taking advantage of you and not helping.

SWG can be on, but it isn't worth running it at 100 trying to maintain the FC if you're just going to drain it - use liquid.

As for why your CYA is this high (assuming it is):
Someone at some point in your pool water's life added dichlor solid shock packets, trichlor pucks or sticks or floaters, or straight CYA powder or liquid. It doesn't break down in the sun, so your CYA only ever goes down when water is splashed or carried or pumped out - so nearly all the CYA that's ever been added is still in there. Any source of FC that says stabilized or conditioned will increase CYA, so be sure to avoid them, as I think you have.

Reminder from Pool School:
CYA - Cyanuric Acid

Cyanuric acid, often called stabilizer or conditioner, both protects FC from sunlight and lowers the effective strength of the FC (by holding some of the FC in reserve). The higher your CYA level, the more FC you need to use to get the same effect. It is important to know your CYA level so you can figure out what FC level to aim for. If you don't have a SWG, CYA is typically kept between 30 and 50ppm. If you have a SWG, CYA is typically kept between 70 and 80ppm.

In nearly all cases the best way to lower CYA is to replace water. If replacement water is extremely expensive you might want to look into a reverse osmosis water treatment.
 

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