Just drained and refilled pool...now what?!

Mollymac

Member
May 3, 2020
11
Shreveport, LA
I am a new pool owner. We purchased a home with a 7 year old, inground, 20,000 gallon, gunite pool with pebble finish. Previous owners had pool company coming weekly to clean and add chemicals. We continued that for the last 6 months and were usually home when they cleaned. I tried to observe what they were doing and learn what they added when algae was growing, how much, etc. When I asked pool guy how he determined how much shock, algaecide, soda ash to add, his answer was "I've just been doing this a long time". Decided to take control of the pool since it did not look great between visits and I had no idea what to add. Bought the Taylor K-2006 test kit. First of all, FC was super low (0.2 ppm) 12 hours after the pool guy shocked it. Chlorine tablet feeder set on 3 on a scale of 1-5. On my initial round of testing, CYA was off the chart. Little black dot disappeared before even getting to the highest reading! Had to dilute sample and double result. I got around 180. Took sample to pool chemical store and they got 153. Went back and looked at all pool cleaning bills which had "test results" for each week. CYA always listed at 40 every week for last 4 months. Obviously, they were not testing it at all!! Drained almost 80% of the pool this weekend and just refilled it. Added one gallon of liquid chlorine last night and turned on the pump overnight. This morning here are my results:

FC 0.4
CC 0.6
pH 7.5
TA - 40
CH - 80
CYA - 40 (I am going to take water sample to pool store to get more accurate reading. My 9 year old son and I had a hard time determining when the black dot completely disappeared)

What do I do now?? Obviously, turned off chlorinator with tablets. I don't want any additional CYA. When I put values in Pool Math app, it tells me to put in a gallon of chlorine. When I slide the SLAM button, it tells my my SLAM Target FC is 16 and it outside recommended range. With 16 in the FC goal, it tells me to put 3 gallons of chlorine in.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Welcome to TFP! :wave: So after all the work to get the CYA down, it appears you are left with an algae bloom in the making. No need to go to the pool store for a second guess of anything, I trust YOUR numbers with the K-2006C. :goodjob: To begin the SLAM Process, it might not hurt to lower the pH just a little more to about 7.2 just to be safe since we don't know how long the SLAM will take. Once the pH is lower, increase the FC to "16" which is your SLAM FC level based on your CYA of 40 as noted on the FC/CYA Chart. Follow all the instructions on the SLAM Process page and you should do fine. Let us know if you have any questions.
 

YippeeSkippy

Mod Squad
LifeTime Supporter
Jan 17, 2012
15,479
Evans, Georgia
WOW Mollymac..... you've really taken charge of this pool. GOOD for YOU! :goodjob: Amazing how clueless pool service folks were to this pool (being nice here, criminal comes to mind also).

You have a couple of choices to make regarding ongoing pool sanitation. Do you want to continue with pucks? I would suggest *not*, but of course its your choice. The downside is that they encourage the CYA to get too high and requires occasional draining and refilling to lower the CYA. Alternatively you can use just liquid chlorine, adding a dose every day or two as your learn your pool's needs. Also based on your testing of FC levels. A lot of folks do this as it adds nothing unknown or unwanted to the pool (aside from a bit of residual salt which every chem leaves behind). Or, for ease and ability to leave on vacation and know the pool isn't going without its required chlorine- you can add a Salt Water Chlorine Generator (SWG) to your equipment pad. It makes the chlorine from salt in the water. I have one and have been able to go out of town for up to 17 days and come back to a sparkling clear sanitized pool (I have a cover which also helps).

Consider your options. How to Chlorinate Your Pool - Trouble Free Pool

Questions? Ask away :). We're happy to help.

Maddie :flower:
 

Mollymac

Member
May 3, 2020
11
Shreveport, LA
WOW Mollymac..... you've really taken charge of this pool. GOOD for YOU! :goodjob: Amazing how clueless pool service folks were to this pool (being nice here, criminal comes to mind also).

You have a couple of choices to make regarding ongoing pool sanitation. Do you want to continue with pucks? I would suggest *not*, but of course its your choice. The downside is that they encourage the CYA to get too high and requires occasional draining and refilling to lower the CYA. Alternatively you can use just liquid chlorine, adding a dose every day or two as your learn your pool's needs. Also based on your testing of FC levels. A lot of folks do this as it adds nothing unknown or unwanted to the pool (aside from a bit of residual salt which every chem leaves behind). Or, for ease and ability to leave on vacation and know the pool isn't going without its required chlorine- you can add a Salt Water Chlorine Generator (SWG) to your equipment pad. It makes the chlorine from salt in the water. I have one and have been able to go out of town for up to 17 days and come back to a sparkling clear sanitized pool (I have a cover which also helps).

Consider your options. How to Chlorinate Your Pool - Trouble Free Pool

Questions? Ask away :). We're happy to help.

Maddie :flower:

What's very strange is that the previous owners told us it was a salt water pool, but once we bought the house and had the existing pool company out to explain the iAqua Link app and the equipment they said, "hmm, there is no salt sensor". Upon a review of the service records, they had only been adding chlorine for at least 2 year prior to our purchase. They don't know when the salt sensor was removed or why. I don't know if the salt cell was bad too. When I discovered the high CYA, I called another pool company to confirm that draining it was the only solution. They suggesting converting it back to salt. I polled my friends on Facebook and 10 out of 12 had salt systems and converted to chlorine. They cited having to replace salt equipment every 2 years, corrosion of pool furniture, etc.
 

Mollymac

Member
May 3, 2020
11
Shreveport, LA
Welcome to TFP! :wave: So after all the work to get the CYA down, it appears you are left with an algae bloom in the making. No need to go to the pool store for a second guess of anything, I trust YOUR numbers with the K-2006C. :goodjob: To begin the SLAM Process, it might not hurt to lower the pH just a little more to about 7.2 just to be safe since we don't know how long the SLAM will take. Once the pH is lower, increase the FC to "16" which is your SLAM FC level based on your CYA of 40 as noted on the FC/CYA Chart. Follow all the instructions on the SLAM Process page and you should do fine. Let us know if you have any questions.

Just got back from pool store. Their readings were very similar to mine (except for FC and TC) My results probably not very accurate because I had to add several scoops of powder to the Taylor K-2006 just to get the water to turn pink so I know FC is very, very low:
FC 0.1
CC 0.42
pH 7.8
TA 41
CH 72
CYA 44

Their suggestions:
Add 25# of calcium (wait 4-6 hours)
Add 20# of Akalinity Up (wait 1-2 hours)
Add 3# Shock

They looked at me like I was crazy when I mentioned liquid chlorine. I did already buy some at Home Depot.

What do I need to do to get the TA and CH up?

**Let me add that the pool company is embarrassed that I discovered the out of control CYA and their cleaner basically never tested it or lied about results. They are giving me a month of cleaning and all chemicals needed to get balanced. Should I have them add whatever is needed to get the TA and CH up? Should I get free Dichlor from them and save my liquid chlorine for after I get my free services and fire them? I told them I am not using tablets.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
I did already buy some at Home Depot.
Perfect! :goodjob: So yes, it's time to SLAM:
1. Lower pH to about 7.2 (orange)
2. Let's continue to use your CYA of 40 as the measuring stick to increase the FC to "16" (FC/CYA Chart)
3. We'll come back to the TA and CH after the SLAM.

Follow the SLAM Process page carefully and it will work. Remove any portable items from the pool like ladders, steps, etc. If you have a pool light with a niche behind it, remove the light as well and clean inside the niche. Let the SLAM FC-level water get in there. Make sure power is OFF to the light before removal. If you have a main drain, check under the cover as well. Drains can get yucky.

Good luck!
 

Mollymac

Member
May 3, 2020
11
Shreveport, LA
Just got back from pool store. Their readings were very similar to mine (except for FC and TC) My results probably not very accurate because I had to add several scoops of powder to the Taylor K-2006 just to get the water to turn pink so I know FC is very, very low:
FC 0.1
CC 0.42
pH 7.8
TA 41
CH 72
CYA 44

Their suggestions:
Add 25# of calcium (wait 4-6 hours)
Add 20# of Akalinity Up (wait 1-2 hours)
Add 3# Shock

They looked at me like I was crazy when I mentioned liquid chlorine. I did already buy some at Home Depot.

What do I need to do to get the TA and CH up?

**Let me add that the pool company is embarrassed that I discovered the out of control CYA and their cleaner basically never tested it or lied about results. They are giving me a month of cleaning and all chemicals needed to get balanced. Should I have them add whatever is needed to get the TA and CH up? Should I get free Dichlor from them and save my liquid chlorine for after I get my free services and fire them? I told them I am not using tablets.
Shows how much the pool company knows. I asked them if the shock contained CYA and they said no - they use Dichlor. Doesn't that contain CYA??
 
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YippeeSkippy

Mod Squad
LifeTime Supporter
Jan 17, 2012
15,479
Evans, Georgia
Tell them you want your credit in new jugs of liquid shock. That is liquid chlorine you'll be able to use it. Kinda hard to imagine how clueless they are about the ingredients in products they sell, but we hear that a LOT.

Do not buy anything called "Alkalinity Increaser"....all that is is baking soda! You can buy big bags of that in the baking goods aisle of Walmart or Costco, at a fraction of the price.

Don't bother tweaking any of your chemicals until after the SLAM process if over.

Maddie :flower:
 

Mollymac

Member
May 3, 2020
11
Shreveport, LA
Tell them you want your credit in new jugs of liquid shock. That is liquid chlorine you'll be able to use it. Kinda hard to imagine how clueless they are about the ingredients in products they sell, but we hear that a LOT.

Do not buy anything called "Alkalinity Increaser"....all that is is baking soda! You can buy big bags of that in the baking goods aisle of Walmart or Costco, at a fraction of the price.

Don't bother tweaking any of your chemicals until after the SLAM process if over.

Maddie :flower:
Thank you! Just added 3.2 gallons of liquid chlorine per the SLAM calculator. How often should I re-test?
 

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YippeeSkippy

Mod Squad
LifeTime Supporter
Jan 17, 2012
15,479
Evans, Georgia
If you can, you can do it every 2 hours if you want. The more often you test, then re-dose based on PoolMath's guide on how much liquid chlorine to add, you'll speed up the entire process. If you can't test and re-dose often, make it at least 3x/day.
What you'll notice is the FC remains longer as the algae is killed off. At first it will chew thru the chlorine but later it lasts longer. That's a good sign progress is happening.

Maddie :flower:
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
35,964
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
I polled my friends on Facebook and 10 out of 12 had salt systems and converted to chlorine. They cited having to replace salt equipment every 2 years, corrosion of pool furniture, etc.
None of that is true if properly maintained. But that is for another thread.
 

Mollymac

Member
May 3, 2020
11
Shreveport, LA
If you can, you can do it every 2 hours if you want. The more often you test, then re-dose based on PoolMath's guide on how much liquid chlorine to add, you'll speed up the entire process. If you can't test and re-dose often, make it at least 3x/day.
What you'll notice is the FC remains longer as the algae is killed off. At first it will chew thru the chlorine but later it lasts longer. That's a good sign progress is happening.

Maddie :flower:
I just tested approx 3 hours after my first SLAM, FC is up to 10.4 with SLAM Target of 16. I added the recommended amount from pool math. Just keep doing this until it gets up to 16? And then...?
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
I added the recommended amount from pool math. Just keep doing this until it gets up to 16? And then...?
Just stick with it. The SLAM Process is indeed an ongoing process that may take several days. Focus on the FC testing as much as required to maintain an FC of 16. It will begin to hold better over time and you won't need test as frequently or add as much. You'll see a pattern. But try to be consistent. And don't forget the other SLAM tasks on that page.
 

wireform

Silver Supporter
In The Industry
Aug 15, 2017
1,959
Spring Valley, NY
Molly,
Just keep it steady and don't over think this. Also don't go above the FC slam level as that's just waste and it won't hasten the slam process. Keep an eye out for the filter gauge to rise when the dead algae starts to clog the filter. Stick around here for the only advice and don't let those facebook guys get in your way.
 

mguzzy

Gold Supporter
Very odd....my first cell lasted 8+ yrs.
I am on year 7.
My first cell made it 9+ years... second cell is at 6 years and chugging along. If the SWG controller is still there it might be an easy task to fire the old one up.. otherwise you will find lots of support here for adding a new from the forum natives here ;)

but lets get your existing pool under control first.

**Let me add that the pool company is embarrassed that I discovered the out of control CYA and their cleaner basically never tested it or lied about results. They are giving me a month of cleaning and all chemicals needed to get balanced. Should I have them add whatever is needed to get the TA and CH up? Should I get free Dichlor from them and save my liquid chlorine for after I get my free services and fire them? I told them I am not using tablets.
Yeah get the chems and then tell them bye bye... Liquid CL and enough CH to get you stable.. you can put it in yourself. :mrgreen:
 
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Mollymac

Member
May 3, 2020
11
Shreveport, LA
Ok, been SLAMming all week. Pool looks beautiful. My target SLAM level is 16. Got up to 16 last evening. This morning it was 14 around 9:30 am. So, I think I still need to keep up the SLAM and then pass the overnight test. CC is 0 and water is crystal clear. Have been running filter pump 24 hrs a day this week.

Just so I understand the next steps, once I pass OCLT, I let it drift down to target FC level. With my CYA at 40, I want it between 3 and 7 according to Pool Math app. So let it drift, then test daily and hopefully I will be adding cups of liquid chlorine every day instead of gallons? How many hours a day should I run my filter pump once my SLAM is over?
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
35,964
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
Once you pass OCLT, maintain your FC in the target range.

For an approximation, you will need to add 76 ounces per day of 10% liquid chlorine per day for 3 ppm.

The time you run your pump will depend on the needs of your infloor pool cleaner and skimming. Just be sure you add the liquid chlorine while the pump is running and will not turn off for 30 minutes or so.
 
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