I've had the SWG for several months. My CYA level is between 60 and 100. When I first started I sought to get the FC level between 6 and 8 a d keep it there. That didn't seem to be too difficult during our "winter" in SW Florida. Summer, however, has been different. It seems anytime my FC level gets below 10-12 I start getting small amounts of green algae on the pool sides and everything goes downhill quickly from there (we all know what that means.) I don't know if it's just the amount of rain, the rain washing through the screen enclosure (yes it gets algae on it too), or the relative jungles my neighbors keep. The bamboo/trees seem to keep alot of dirt and some gets transferred to my pool enclosure. Soooooo, I plan to try and keep my FC in the 10-13 range a d see what happens. Plolyquats maybe if this doesn't work. Just thought I'd share my ongoing travails!
SWG chlorine levels
- Thread starter fishing
- Start date
What test kit are you using? Is it one of these: Test Kits Compared
Because right off the bat you should be able to know the CYA much better than 60-100 ... that is key to knowing the proper FC level according to the FC/CYA Levels
Once you have ANY sign of algae, you need to completely follow the SLAM Process process to eradicate it, after which, you should be able to maintain normal FC levels without the algae returning.
Please fill out your signature with you pool and equipment details.
Because right off the bat you should be able to know the CYA much better than 60-100 ... that is key to knowing the proper FC level according to the FC/CYA Levels
Once you have ANY sign of algae, you need to completely follow the SLAM Process process to eradicate it, after which, you should be able to maintain normal FC levels without the algae returning.
Please fill out your signature with you pool and equipment details.
Well, the slide tests don't show calibration between 60 and 100. It's about halfway between. I know what the chart says. And I'm in the process of slamming as I type. This will be the third slam in the last 3 months. I have K1515A, K1766, K2005.
Steve_in_C
Bronze Supporter
Minimum FC is based on your CYA. Because your testing inaccuracy (60-100), you can't accurately know how much your FC needs to be. You may be having problems because of this. You could try to a dilution test with 1:1 pool to tap water and retest. Multiply results by 2. FC minimum for 60 would 5, and TFP does not recommend CYA of 100 at all (therefore undefined). The low accuracy of your CYA testing is probably why you are failing. You could get another comparator for a more accurate reading of the turbidimetric CYA test. Looks like your FC test is OK. The CYA standard of 50ppm will help you perform the test correctly - available from Taylor and TFT.
Looks like Taylor and TFT have comparators for CYA that have graduations between 60 and 100 for more accuracy. It's the cornerstone of your FC goal and too important not to know.
Looks like Taylor and TFT have comparators for CYA that have graduations between 60 and 100 for more accuracy. It's the cornerstone of your FC goal and too important not to know.
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I thought the CYA test in the K-2005 had lines from 30ppm up to 100ppm at every 10ppm.
I have the standard. The comparitor is not calibrated between 60 and 100. It's not an issue of not performing the test correctly. I use a slam target of over 30 for my FC, so I'm pretty sure that part is working.
What's wrong with the other one? Lots of people in this forum use them.Well, there's your problem
Edit: although having cleaned the camparitor tube, it does seem to be easier to use.
Steve_in_C
Bronze Supporter
It may be OK if in the range of your comparator. But if not, it's unacceptable. Knowing an accurate CYA is the cornerstone of this method.
So if others have a CYA that is within the calibrated range of your comparator, they can get good results. If your's is reading a range outside your comparator, you can't. Try weighing yourself on a scale that has no calibration points between 100 and 300 pounds. You can't get a good weight. However if you only weight 90 pounds, it might be valid.
So if others have a CYA that is within the calibrated range of your comparator, they can get good results. If your's is reading a range outside your comparator, you can't. Try weighing yourself on a scale that has no calibration points between 100 and 300 pounds. You can't get a good weight. However if you only weight 90 pounds, it might be valid.
The problem is that you are telling us your CYA is between 60 and 100. Other members report a CYA that 70 or 80, not a 40ppm window. You must know your CYA to know the proper FC level to maintain.
At this point the best we can tell you is to assume a CYA of 100ppm and use the FC targets for SLAM and maintenance for that level.
And of course remember that when the FC > 10ppm, the pH test does not work and gives artificially high values.
At this point the best we can tell you is to assume a CYA of 100ppm and use the FC targets for SLAM and maintenance for that level.
And of course remember that when the FC > 10ppm, the pH test does not work and gives artificially high values.
Fish,
I see the problem slightly different... If you have had to SLAM three times in three months, then you are never really completed the SLAM.. Once you complete a SLAM algae is not coming back as long as you keep your FC up.. I would think that even if all you know is that the CYA is above 60 and below a 100 that would be good enough in most cases..
I believe that you "think" the SLAM is done, but some unseen algae is still remaining in your pool.. Behind the light or under a ladder or?? My guess is that you are not really brushing as much as you need to..
Running at 10 ppm of FC or so, just keeps the algae in check, but you don't want algae to be "in check" you want it all gone.
I suggest that you SLAM for a couple of extra days after you think the SLAM is done and brush like heck.. If this were my pool, and kept getting algae, the light would be coming out and I'd be looking for any non obvious hiding places...
Thanks,
Jim R.
I see the problem slightly different... If you have had to SLAM three times in three months, then you are never really completed the SLAM.. Once you complete a SLAM algae is not coming back as long as you keep your FC up.. I would think that even if all you know is that the CYA is above 60 and below a 100 that would be good enough in most cases..
I believe that you "think" the SLAM is done, but some unseen algae is still remaining in your pool.. Behind the light or under a ladder or?? My guess is that you are not really brushing as much as you need to..
Running at 10 ppm of FC or so, just keeps the algae in check, but you don't want algae to be "in check" you want it all gone.
I suggest that you SLAM for a couple of extra days after you think the SLAM is done and brush like heck.. If this were my pool, and kept getting algae, the light would be coming out and I'd be looking for any non obvious hiding places...
Thanks,
Jim R.
I maintain that any reading on these plastic tubes is somewhat subjective. I've seen people post readings of 45. That's simply not discernible. The slide comparitor doesn't have calibration mark's between those two values. I know what FC target to use for CYA levels of 60, 70, and 80. Extrapolation will get me the rest of the way.
I agree. Although my lights are nicheless, I believe the SLAM process was not completed correctly. Gonna try again. It didn't help that I had to go out of town just as the pool was drifting to a lower FC level. I need to be able to see what happens at what I think was the tipping point. I was just sharing my process.
You are correct, then then we tell them to round up to 50ppm. So by that logic, should you round up to 100ppm? Depends on where the dot is disappearing when you slide it around. Post up a picture showing that location and the scale and we would at least have a little better idea if it is on the low or high end of that range.
In any case, I think you are on the right track that the algae was never fully eradicated and that is why it keep coming back even at higher FC levels.
I didn't mean for this to get into a CYA test discussion. But ok, unless a anyone is using graduated pipettes/cylinders there is no way to get any closer than 10% accuracy on any of the CYA tests. And I think that's being charitable. So yeah, I know what the chart says about the relationship between CYA and FC. It's just that some of it is gonna be a "best guess." Now that being said, the FAS/DPD test (among others) seems much more accurate. Anyway, I'm still on the hunt for the origin. I continue to think the algae on the screen enclosure could be entering the pool during the monsoons.
Algae could certainly fall off the screen into the pool, but if the FC level is properly maintained, then it will be killed off before it multiplies.
Haha! That's where this all started. It was maintained. The SWG was operating normally and was stable for at least a week with no fluctuations. But we had no rain. I left for a week and come back to FC level of 2 and dull water with some green algae. And it rained quite a bit while I was gone. Somehow I either didn't kill it all last time or it found it's way back in. That's my dilemma.
That may be next. A 50/50 bleach mix in a pump or hose sprayer might work. I'm not a huge fan of these enclosures but it was here when we got here.