Working toward SLAM - any words of encouragement?

[unit335]

I am a new pool owner and inherited a pool with my home purchase. Upon purchase, at pool opening water was CRYSTAL clear. Under my care it started to become cloudy. What was going on? TFP taught us to test the water and we determined that CYA was off the charts. I estimate about 150-180ppm. So at this point I understood the forming cloudiness was related to me not maintining the correct FC/CYA ratio.

Now I am working to reduce CYA. Currently at 92ppm targeting 60ppm to begin SLAM. During the CYA reduction process (I am doing a series of drains/refills to maintain a high water level) the pool has become much cloudier and green. But I am staying the course, trying to maintain a FC level and pH appropriate for 90ppm CYA to help prevent total runaway algae growth, and am basically holding fast until Sunday morning when CYA should be in the recommended zone to start SLAM.

Did a deep clean of our sand filter last weekend, so I hope I am doing ok there.

Any tips or words of encouragement for me at this point?

 

[V___25]

Hello there! Doing a SLAM with a CYA of 60 is going to be tough and require lots of chlorine. Doing a series of smaller drains is going to take more water each time to lower CYA. Can you do one larger drain and refill? Or have you read the No drain water exchange article? That may be a way to go also.

 

[unit335]

Hello there! Doing a SLAM with a CYA of 60 is going to be tough and require lots of chlorine. Doing a series of smaller drains is going to take more water each time to lower CYA. Can you do one larger drain and refill? Or have you read the No drain water exchange article? That may be a way to go also.

I asked some local folks about doing a large drain and it was not recommended. One guy's water level went too low one winter and he had to have his pool repaired. So yes, I am working against the inefficiency of doing percentage-wise drains. It's taking a long time...ugh.

After 9 more drain/fill cycles I should be at approx. 59 ppm CYA, which is barely inside the recommended SLAM zone. I'm very interested in the no drain exchange article...I'm looking for it now. If you can put your finger on it quickly could you link it?

 

[unit335]

Hello there! Doing a SLAM with a CYA of 60 is going to be tough and require lots of chlorine. Doing a series of smaller drains is going to take more water each time to lower CYA. Can you do one larger drain and refill? Or have you read the No drain water exchange article? That may be a way to go also.

Ok I found the no drain article. Yes, that's essentially exactly what I'm doing
Just for fun I'll add some numbers for you haha.

For the initial CYA level I measured I estimate I needed to replace 75% of my pool water. Pool is 40k gallons. My water hose fills at 300 gallons an hour.... So yeah, not a huge fan of previous owner's chlorine tab usage!

 

[V___25]

I hear ya with the prior owners tab usage - that was my situation too 3 years ago. Good for you for getting a handle on it! Once you get the SLAM started, just make sure your bring your pool owner patience - sand filters are the slowest at clearing dead algae so it will take some time.

 

[unit335]

I hear ya with the prior owners tab usage - that was my situation too 3 years ago. Good for you for getting a handle on it! Once you get the SLAM started, just make sure your bring your pool owner patience - sand filters are the slowest at clearing dead algae so it will take some time.

Thank you I'll try to be patient! As long as it's presentable 3 weeks from now when we will have company

 

[Getitrite]

TFP taught us to test the water and we determined that CYA was off the charts. I estimate about 150-180ppm.

Was that determined with a diluted CYA test? (I need to try this myself, for educational purposes. Need to create artificially high sample so I can see it "live".) I would hope the diluted test should be able to yield a result more accurately than +- 30?

working to reduce CYA. Currently at 92ppm targeting 60ppm to begin SLAM

cycles I should be at approx. 59 ppm CYA, which is barely inside the recommended SLAM zone

CYA results are Rounded UP. One should not interpolate between the graduated markings. (Hence, the rounding practice.)

 

[SoCalTFP]

Getting the CYA down is a big priority, no matter how many drains it takes. There is a good article on here about drain/fill you should check out. It doesn’t reduce itself outside of splashing or rain.

I’d also recommend not going with a company. You’ll be dealing with the same stuff in no time, that’s how I ended up here.

 

[Kaylee34]

How much are you draining at one go?

 

[SoCalTFP]

Draining - Further Reading

www.troublefreepool.com

Here’s the draining link too, there might be another that goes into the no drain or drain/fill method more in depth.

 

[unit335]

Was that determined with a diluted CYA test? (I need to try this myself, for educational purposes. Need to create artificially high sample so I can see it "live".) I would hope the diluted test should be able to yield a result more accurately than +- 30?




CYA results are Rounded UP. One should not interpolate between the graduated markings. (Hence, the rounding practice.)

I'm not sure what the diluted test is - so I'll just describe that I used the Taylor kit test comparator test. The only reason I couldn't accurately measure the beginning CYA level is because it was literally off the scale. By a lot. Now that the result is on the scale I guess the biggest inaccuracy is whenever the testing person decides when they can't see the dot anymore. Between my wife and I I'd give it an accuracy to within 5ppm or so. But yeah, I'll be rounding that result up when executing the SLAM. Thanks for the reminder on that.

 

[unit335]

Draining - Further Reading

www.troublefreepool.com

Here’s the draining link too, there might be another that goes into the no drain or drain/fill method more in depth.

Great! I was doing drain and fill like I said, but it so happened a got a small utility pump that is pretty closely rate matched to the output of my water hose, so I have the exact 'No Drain' method running now. Should be under 60 ppm CYA by Sunday morning. I was planning on executing SLAM procedure at 60ppm, should I go lower?

 

[unit335]

How much are you draining at one go?

about 1400 gallons. Running a 'for real' no drain setup now. So now I can let it run all night.

 

[SoCalTFP]

Good to hear I was worried you were going to try to SLAM at your current CYA, with your big pool would have been ~16 gallons to go from 0 to SLAM level!

 

[Getitrite]

If you CYA is 90 or Higher and Just call it as you see it

 

[unit335]

If you CYA is 90 or Higher and Just call it as you see it

That's a nifty trick for measuring high CYA. I'm low enough now to be on scale but that would have been fun to try

 

[unit335]

Good to hear I was worried you were going to try to SLAM at your current CYA, with your big pool would have been ~16 gallons to go from 0 to SLAM level!

Oh yeah the numbers get pretty stupid at high CYA. Even just regular maintenance requires a lot more chlorine. I'd rather be swimming in my pool right now but since we just got the house we want to get it right from the start and hopefully never have to do all this crazy draining again.