New to Pools - Pool Closed for FOUR YEARS.....HELP!
- Thread starter fndngserenity
- Start date
Help Please!
Started slam today. Added a bunch and wasn't quite there so added a little more and now we are at 17.5 FC instead of the targeted 14.........CYA is at 35.
Do I need to add more CYA or should I just leave everything as it is?
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Started slam today. Added a bunch and wasn't quite there so added a little more and now we are at 17.5 FC instead of the targeted 14.........CYA is at 35.
Do I need to add more CYA or should I just leave everything as it is?
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While you will want to avoid overshooting it in the future, that should not be a problem. Just let it fall back below 14 before you dose again and continue as normal.
OK, phew! Thank you 
I guess I will try bringing my pool volume down a couple thousand in my next pool math because everything has been too high using my current volume estimate.
Thanks again!!!
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I guess I will try bringing my pool volume down a couple thousand in my next pool math because everything has been too high using my current volume estimate. Thanks again!!!
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First night of slam results!
First off, I would like to say that my pool volume estimated at 26,700 was obviously too high because all of my numbers have been skewed since.
With that said, last night FC was 17.5 about an hour after adding chlorine. It actually went up a little more and target was 14.
FC: 19
PH: 7.2
CH: 150
TA: dropped from 110-100
CYA: dropped from 35 to 30
I forgot to do CC and TC. I can get those if necessary.
So, now I am not sure what to do. It says to stop slam when CYA is under 0.5. My CYA is way above that.
I am not sure what I should be doing at this point.
Thank you!
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First off, I would like to say that my pool volume estimated at 26,700 was obviously too high because all of my numbers have been skewed since.
With that said, last night FC was 17.5 about an hour after adding chlorine. It actually went up a little more and target was 14.
FC: 19
PH: 7.2
CH: 150
TA: dropped from 110-100
CYA: dropped from 35 to 30
I forgot to do CC and TC. I can get those if necessary.
So, now I am not sure what to do. It says to stop slam when CYA is under 0.5. My CYA is way above that.
I am not sure what I should be doing at this point.
Thank you!
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- Mar 24, 2014
- 2,455
- Pool Size
- 32000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool SJ-55
No, you've misread slightly, the criteria to stop/ finish a slam is when your CC is .5 or less, you haven't lost any FC overnight, and your water is clear. CC (stands for combined chlorine...the second step after reading Free Chlorine..."cc" not "cya").
Your CYA is a "stable" reading in that you want a) to keep it at this level...it only reduces a bit with splash out or backwashing, so normally only check it once a month r so) and
B) After the slam, you want to dose to the CYA:FC ratio shown in the link in my signature -- that formula is the future key to a trouble free pool
Oops, cross posted with mr Bruce
Oops! Thanks for the correction OK so I just have to keep my FC at the slam CYA level, correct? So at this time, keep testing and don't let it fall below that, right?
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OK so I just have to keep my FC at the slam CYA level, correct? So at this time, keep testing and don't let it fall below that, right?Sent from my SM-G800R4 using Tapatalk
- Mar 24, 2014
- 2,455
- Pool Size
- 32000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool SJ-55
You might be done but it can't hurt to go one more day! What is your CC and how does the water look?
Oops! Thanks for the correction
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Yes, test FC and add back to shock level as often as you can, 3 times per day minimum. And brush the pool daily or more. Once the water is crystal clear, can read heads or tails on a dime in the deep end, then test CC and do the OCLT.
During a SLAM, especially at the beginning, it is hard to get a good CYA reading. The CYA test depends on the "cloudiness" of the sample after mixing with the test chemicals to figure out how much CYA is in the water. In the CYA test, more CYA in the sample makes more cloudiness after you add the test chemical, and it takes less water in the tube to obscure the dot. So the CYA test reading is a function of the "depth" of water in the tube when the dot is obscured, and you get your reading from the side of the tube. So if your pool water is cloudy to start with, which is often the case when you are starting to SLAM, that cloudiness "adds" to the "cloudiness" you are trying to "measure" to test CYA. That makes it take less water in the tube to obscure the dot and gives you a falsely high result. That is why people say to calculate the amount of CYA you need to add to get to a certain CYA level, add that much to the pool, then assume that you are at the calculated CYA level (instead of testing) to pick the appropriate FC level for the SLAM from the CYA/chlorine chart. My guess is that your CYA did not really change. Instead, I would expect that your CYA test before was showing higher than actual due to the cloudiness of the water in the pool. Now that the pool is clearing up, that error in the CYA test is changing, and your test result is getting closer to your actual CYA level. I have seen that with my pool during a SLAM. The other thing is that the CYA test itself is not terribly accurate. A change of 5 could easily be within the margin of error for that test.
Some of the real experts may correct me, but I personally do not worry about the FC being above the SLAM target during the SLAM. In fact, I try to keep it a bit high so that when it drops, it never gets below the SLAM level. I do not think you need to worry at all about being at 19. If you get to the end of the SLAM, and you need to lower the FC to safe swim levels (at or below the SLAM level), there are chemicals that will drop the FC. Normally, I can just leave the pool open in the sun for a day, and it will come down.
As far as FC rising overnight, I would say there are two things that could do that. First, depending on how well your pool circulates, the chlorine may not have been completely mixed through the pool when you tested after adding. Second, it is not unusual to get some variation in the test. In other words, it may be variation in your testing methods, not variation in the actual level. Don't worry about that too much right now. You want to get good repeatable results. But during a SLAM, when adding a bunch of drops, I find that I add the drops more quickly, which can lead to the drop size varying, and some variability in the test results. To get good reliable results, you want to be sure and get a nice repeatable sample volume in the test cylinder. I got a 10ml syringe from the pharmacy and use that to get an accurate test volume. You also want to add the drops nice and slow so they fully form and drop off the bottle the same every time. I also believe using a speed stir helps a ton with repeatable results. But over time, you will get more and more accurate. For right now, I do not think it is anything to be too worried about. If you want to see how precise your testing is, repeat the test a couple times from the same sample. Otherwise, the fact that it seems to have come up a bit is a good thing since at least it is not dropping like a rock. Oh, one other thing it could be - your neighbor could have come over and snuck in and added bleach while you were sleeping. Do you have any neighbors that would want to mess with your head??
Let's talk CC a minute. As contaminants are consumed by the FC (free, as in available to disinfect, chlorine), the FC is converted to CC (combined, as in chemically bound to some contaminant it is "eating", chlorine). Others can explain the chemistry better than I can here, but the CC is then broken down further after some time and "disappears." So while the FC is still actively working to kill all the algae and other organics in your pool, CC is constantly being formed. So CC is a sign that something is still in the water, and that the FC is still working to get rid of it. Once the organics are all gone, and the FC is no longer actively working to break them down, CC stops forming. And after a bit of time, the CC will break down the rest of the way, and your CC will drop below 0.5. That is why it is one of the criteria for the SLAM being done - it tells you when the FC has finished doing its job.
Let's talk the OCLT test a minute now. Basically, there are two things that consume FC in your pool - contaminants (algae and other organics and so forth), and sunlight. As long as there are organics in the pool being consumed by the FC, the FC will keep dropping. Once all the organics have been removed, the FC will stay steady except for what is broken down by the sunlight. So you test the FC in the evening after sunset, then again early in the morning before sunrise. That way, you know nothing was broken down by the sun. If there is no change (or very minimal change), the organics are all gone. If there is a drop, there is still more work for the FC to do, and the SLAM continues.
Some of the real experts may correct me, but I personally do not worry about the FC being above the SLAM target during the SLAM. In fact, I try to keep it a bit high so that when it drops, it never gets below the SLAM level. I do not think you need to worry at all about being at 19. If you get to the end of the SLAM, and you need to lower the FC to safe swim levels (at or below the SLAM level), there are chemicals that will drop the FC. Normally, I can just leave the pool open in the sun for a day, and it will come down.
As far as FC rising overnight, I would say there are two things that could do that. First, depending on how well your pool circulates, the chlorine may not have been completely mixed through the pool when you tested after adding. Second, it is not unusual to get some variation in the test. In other words, it may be variation in your testing methods, not variation in the actual level. Don't worry about that too much right now. You want to get good repeatable results. But during a SLAM, when adding a bunch of drops, I find that I add the drops more quickly, which can lead to the drop size varying, and some variability in the test results. To get good reliable results, you want to be sure and get a nice repeatable sample volume in the test cylinder. I got a 10ml syringe from the pharmacy and use that to get an accurate test volume. You also want to add the drops nice and slow so they fully form and drop off the bottle the same every time. I also believe using a speed stir helps a ton with repeatable results. But over time, you will get more and more accurate. For right now, I do not think it is anything to be too worried about. If you want to see how precise your testing is, repeat the test a couple times from the same sample. Otherwise, the fact that it seems to have come up a bit is a good thing since at least it is not dropping like a rock. Oh, one other thing it could be - your neighbor could have come over and snuck in and added bleach while you were sleeping. Do you have any neighbors that would want to mess with your head??
Let's talk CC a minute. As contaminants are consumed by the FC (free, as in available to disinfect, chlorine), the FC is converted to CC (combined, as in chemically bound to some contaminant it is "eating", chlorine). Others can explain the chemistry better than I can here, but the CC is then broken down further after some time and "disappears." So while the FC is still actively working to kill all the algae and other organics in your pool, CC is constantly being formed. So CC is a sign that something is still in the water, and that the FC is still working to get rid of it. Once the organics are all gone, and the FC is no longer actively working to break them down, CC stops forming. And after a bit of time, the CC will break down the rest of the way, and your CC will drop below 0.5. That is why it is one of the criteria for the SLAM being done - it tells you when the FC has finished doing its job.
Let's talk the OCLT test a minute now. Basically, there are two things that consume FC in your pool - contaminants (algae and other organics and so forth), and sunlight. As long as there are organics in the pool being consumed by the FC, the FC will keep dropping. Once all the organics have been removed, the FC will stay steady except for what is broken down by the sunlight. So you test the FC in the evening after sunset, then again early in the morning before sunrise. That way, you know nothing was broken down by the sun. If there is no change (or very minimal change), the organics are all gone. If there is a drop, there is still more work for the FC to do, and the SLAM continues.
We have found that the CYA test is not really affected by the clearness of the pool water. The pool would have to be ridiculously dark for it to actually have an impact on the turbidity test for the CYA.
We also do not recommend raising the FC shock level well above shock level. The shock levels targets are chosen by Design and there's no need to overshoot..
We also do not recommend raising the FC shock level well above shock level. The shock levels targets are chosen by Design and there's no need to overshoot..
Jason, thanks for the additional info. I swear I have seen an effect on the CYA test when my pool was so cloudy I could not see my hand 12" under the surface, but that may have just been my imagination and some wishful thinking. In any case, the CYA test is fairly inaccurate, isn't it? Would a change of 5 in the CYA be anything to be concerned about?
Why do we tell people to add CYA based on PoolMath, then assume that calculated level for determining the target SLAM level of FC rather than testing the CYA level?
Regarding overshooting the SLAM target for FC, how much over is OK? If we are trying to keep the FC at or above the SLAM target, but we do not want to go over the target, that makes for a very very narrow window to hold the FC. Or is the SLAM target such that it is effective even if we drop several ppm below the target before the next test and dose of chlorine?
Thanks again
Heather - if I am confusing you, I apologize. I just noticed you were in the middle of the process and not getting a lot of quick responses, so I thought I would jump in. Hopefully, I have not steered you wrong.
Why do we tell people to add CYA based on PoolMath, then assume that calculated level for determining the target SLAM level of FC rather than testing the CYA level?
Regarding overshooting the SLAM target for FC, how much over is OK? If we are trying to keep the FC at or above the SLAM target, but we do not want to go over the target, that makes for a very very narrow window to hold the FC. Or is the SLAM target such that it is effective even if we drop several ppm below the target before the next test and dose of chlorine?
Thanks again
Heather - if I am confusing you, I apologize. I just noticed you were in the middle of the process and not getting a lot of quick responses, so I thought I would jump in. Hopefully, I have not steered you wrong.
If it says "at or above SLAM level" anywhere please let us know so it can be changed, that is incorrect. You target SLAM level and treat that as the maximum. That doesn't mean 1 ppm above is dangerous, but the more you go north of the limit the more you put things at risk. You dose to get to that target, and then test as often as every hour or two in an attempt to keep it there. The less you let it fall between dosing the faster the SLAM will go, but algae is always being killed at any level above the minimum FC for your CYA.
Remember, the SLAM level is considered the upper limit of the safe range, you want to avoid exceeding it.
Donldson - thanks for the clarification. I do not remember ever reading "at or above SLAM level" anywhere. Reading the SLAM procedure again, it does not say "at" or "at or above" or "at or below" or anything specific. So it was my own assumption that the SLAM level was the minimum to maintain. So I had always figured I should be at or slightly above that level to keep the SLAM going. But what the SLAM level really represents is the maximum safe level for FC. And since the algae is killed more quickly at higher concentrations, we dose up to the maximum safe limit to kill the algae as quickly as possible. That makes sense. Thanks.
So the complete answer is to bring the FC up to SLAM level, and adjust as frequently as possible to keep it as close as possible to that level. When it drops below SLAM level, it does not make things go backwards as long as it stays above minimum FC for the given level of CYA. However, the speed with which the algae is killed is faster the closer you can stay to the SLAM target.
Heather, as I said originally, "some of the real experts may correct me," and they did. Now we both have the real answer.
Thanks again, Jason and Donldson.
So the complete answer is to bring the FC up to SLAM level, and adjust as frequently as possible to keep it as close as possible to that level. When it drops below SLAM level, it does not make things go backwards as long as it stays above minimum FC for the given level of CYA. However, the speed with which the algae is killed is faster the closer you can stay to the SLAM target.
Heather, as I said originally, "some of the real experts may correct me," and they did. Now we both have the real answer.
Thanks again, Jason and Donldson.
On the shallow end I can see the print at the bottom.....on the deep end I can sort of see print but then there is this whitish/yellowish spot.....almost like a cloud or something. I tried to get you all a photo of the cloudy spot but it doesn't really like to have its picture taken [emoji12]
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EVENING UPDATE ON SLAM:
Good evening everyone! I am on day two of my SLAM and all most all of my numbers have decreased. The shock level fell a little too far but I've just added some more to it.
PH: 7.2
FC: 11 (SLAM target 12). Just added some more chlorine.
CC: 0.5
TC: 11.5
CH: 125 - IS THIS OK? When I'm in pool math, it is calling for a much higher amount. Do I need to worry about this right now?
CYA: 30
TA: 90
Nothing has really changed with the "look"of the water. We will keep brushing, vacuuming, etc. and ensuring we're maintaining the SLAM FC level.
Also, one other random question. In pool math, when I select that I want to use the TFP goals, is that what is entered into the goal column OR, is that the written goals that say for example: PH goal is 7.5 - 7.8 and then CH: it says 0 to 350 but the goal that populates into the goal column is 260 so I was just curious which goal is the actual TFP goal.
Thanks!
Good evening everyone! I am on day two of my SLAM and all most all of my numbers have decreased. The shock level fell a little too far but I've just added some more to it.
PH: 7.2
FC: 11 (SLAM target 12). Just added some more chlorine.
CC: 0.5
TC: 11.5
CH: 125 - IS THIS OK? When I'm in pool math, it is calling for a much higher amount. Do I need to worry about this right now?
CYA: 30
TA: 90
Nothing has really changed with the "look"of the water. We will keep brushing, vacuuming, etc. and ensuring we're maintaining the SLAM FC level.
Also, one other random question. In pool math, when I select that I want to use the TFP goals, is that what is entered into the goal column OR, is that the written goals that say for example: PH goal is 7.5 - 7.8 and then CH: it says 0 to 350 but the goal that populates into the goal column is 260 so I was just curious which goal is the actual TFP goal.
Thanks!
No worries bkfamily1. I appreciate the help! I'm just reading everything and taking it all in. There is so much to learn. Hopefully I will have it all down one day ......before I kill my pool. LOL
I'm just reading everything and taking it all in. There is so much to learn. Hopefully I will have it all down one day ......before I kill my pool. LOL