Opened pool, water is NASTY!

[Josh1466]

This is our first year opening the pool. Had a mesh cover on over the winter, lots of leaves sat on the top, which was touching the water and a fair amount got under the cover and into the pool. Water had been clear through the winter as I checked levels and pumped water out to stay below the skimmers. A few weeks ago we had about 3 80 degree days followed by 2 weeks of rain and daytime temps in the 40s with lows in the 20s. I looked at the pool last night when it finally quit raining, and now I have a brown swamp. I have water coming this evening.

I’m planning on getting as many of the leaves and other debris out as possible, getting the pump going and starting a SLAM right away.
Here are my test numbers from today using the TF-100

FC: 0
pH: 6.8
TA: 10
CH: 50
CYA: 0

When I closed I had the following:
FC: 9.5
pH: 7.8
TA: 110
CYA: 70

I’m a little concerned about the CYA. My water level stayed just fine, so I don‘t think I have a leak. I did pump some water off over the winter but not that much. Does it have to do with the lack of chlorine?

Do I need to add CYA to make sure the SLAM works? And what levels should I work on correcting now VS waiting until the SLAM is done?

SWG is off and I’ll be using liquid chlorine for the SLAM.

 

[Texas Splash]

I would do a couple things in preparation for the SLAM and BEFORE you add stabilizer:
1 - Increase the pH to about 7.2. Anything below 7.0 is too low.
2 - Add about 4-5 ppm of liquid chlorine and then test again in about 30 minutes. Hopefully you still have some FC in there. If not, then we may have to coach you through a more aggressive approach to ensure the FC and CYA will hold. So let us know if the FC completely disappears really fast.

Once you have done those two things and the FC appears to be holding fairly well for at least 30 minutes or so, then you can add stabilizer for a CYA target of 30 and increase the FC to the corresponding SLAM level.

Let us know how it goes or if you have any questions.

 

[Josh1466]

I’ll see what I can do. I have a lot of leaves and other organic stuff to get out of there before I add chlorine. I also have to wait for my water to be delivered to get it above the skimmers so I can add chemicals.

 

[Bperry]

I’ll see what I can do. I have a lot of leaves and other organic stuff to get out of there before I add chlorine. I also have to wait for my water to be delivered to get it above the skimmers so I can add chemicals.

Just get as much junk out as best you can while you do the above. It also doesn’t help you now but consider opening it much earlier next year. It’ll save you from a swamp. I open mine in early March even though no one will swim.

 

[ajw22]

Ignore water chemistry without the pump running.

You have stratified water that needs to be mixed for 24 hours with the pump running before you can get a valid test.

 

[Josh1466]

Just get as much junk out as best you can while you do the above. It also doesn’t help you now but consider opening it much earlier next year. It’ll save you from a swamp. I open mine in early March even though no one will swim.

We just installed the pool last year so judging when to open it was a bit of a guess this year. The weather didn’t make it easy. We had a few 80 degree days the second week of April and snow earlier this week.

 

[Josh1466]

Here’s where things stand this morning:
The pump has been running about 12 hours, this morning’s test results were the same as yesterday, with the exception of TA which is up to 50.

I added washing soda to increase the pH and added what pool math recommended to get to a FC level of 5 ppm. 30 minutes later the OTO test said I had between 2 and 3 PPM. The FAS/DPD test said 0.5.

The first gallon of chlorine was from last year so it was probably not as stong as advertised on the bottle. There’s still quite a lot of leaves and junk on the bottom (I think, still can’t see it) so I’m not sure how quickly that will eat up chlorine.

 

[Texas Splash]

So it sounds as if you have "some" chlorine still in the water. In that case, go ahead and add 30 ppm of stabilizer, increase and maintain your FC at 12, and continue with the SLAM Process. Best to knock it out now before the water gets much warmer. Focus on the FC and all the details of the SLAM Process page and you should do well. Also, the OTO is a total of FC and CC, so not the best to gauge your FC level. use your FAS-DPD form now on. It's much better.

 

[Josh1466]

I tested everything again after the addition of the washing soda and before I started raising the FC to the SLAM level. I found that my pH was up to 7.5, and my CYA was at 50. Does the pH affect the CYA reading? I'm just curious why it showed 0 before and now reads 50?

Anyway, I used the SLAM calculator and targeted a FC of 20 ppm because of the CYA level and it seems to be working. I can see the entire bottom now, and I couldn't this morning. The water has gone from a nasty brown to a slightly less nasty green, so I’m calling that progress!

 

[Bperry]

I tested everything again after the addition of the washing soda and before I started raising the FC to the SLAM level. I found that my pH was up to 7.5, and my CYA was at 50. Does the pH affect the CYA reading? I'm just curious why it showed 0 before and now reads 50?

Anyway, I used the SLAM calculator and targeted a FC of 20 ppm because of the CYA level and it seems to be working. I can see the entire bottom now, and I couldn't this morning. The water has gone from a nasty brown to a slightly less nasty green, so I’m calling that progress!

If the water was nasty brown then that could be making the dot harder to see which would make the CYA read higher? Total guess though.

 

[Josh1466]

If the water was nasty brown then that could be making the dot harder to see which would make the CYA read higher? Total guess though.

Water was nasty brown for both tests. Also, in the small quantity needed for the CYA test, it looked clear.

 

[Mdragger88]

Let the cya sample come to room temp before performing the test. It is the only one that is sensitive to cold water temps.
Then do the test outdoors in bright light if possible.

 

[IceShadow]

Could have been the water wasn’t mixed enough, or was too cold when the CYA test was done.

 

[Josh1466]

I think my SLAM is over! FC was the same this morning as last night, CC was 0.5 and the water looks clear. I figured out how to attach pictures so I figured I’d throw up a few to show the progress.

 

[Texas Splash]

Wow! Quite the change. Great job.

 

[Josh1466]

Wow! Quite the change. Great job.

Thanks! It's not bad for just under a week. Certainly couldn't have done it without the forum. Hoping from this point on, keeping my water clear and clean is as easy as it was last year. The TFP methodology works!