Test kit in ... let the SLAMing begin!

[needsajet]

That's good It was a hot one today

Yeh CYA is a frustrating pain, but for now, your tending to read low. That's just a trend, not a comment on what you're doing. Lots of people struggle with the test.

So your reading of 38... we just call that 40. You're tending low, so it's probably somewhere closer to 60.

All I can suggest about the test is to leave it sit for a few minutes and see if it looks any different, but the efforts you've gone to already are terrific.

You get the vast majority of the CYA benefit when you get to 30 and above, so I would just leave it a while and test again in a week. As you say, let your FC drift down a bit more, but even worst case of CYA 30, you're safe to swim up to 12, so all is good. In case the CYA is higher, yep, use a bit higher range for day to day. At 60 ppm CYA, I would use about 4 to 8 ppm FC for your pool.

The best thing is just a 2 ppm FC drop, and that's a highly reliable test. That's great news

 

[kimkats]

CYA = Oh how I dislike this test!

Here are my ideas for you and your pool with this test. When you are looking at the dot GLANCE only. Do not stare at it. Just GLANCE in then look away. I pour to each line, GLANCE in, move to next line if I can see the dot. Us the bigger number if you think it is between two numbers.

Use the standard regent to "ground" your testing. If you stand HERE with this light the standard says it is XX. Make a note of how far "off" it is from the 50 it should be. Now do your pool water in the same place with the same lighting and adjust it according to your standard testing.

Do NOT stress this test. There is a +/- to it so it is all good. You will find how much CYA your pool needs to keep some of the FC in it all day.

I hope this helps

Kim

 

[buballodingo]

CYA = Oh how I dislike this test!

Here are my ideas for you and your pool with this test. When you are looking at the dot GLANCE only. Do not stare at it. Just GLANCE in then look away. I pour to each line, GLANCE in, move to next line if I can see the dot. Us the bigger number if you think it is between two numbers.

Use the standard regent to "ground" your testing. If you stand HERE with this light the standard says it is XX. Make a note of how far "off" it is from the 50 it should be. Now do your pool water in the same place with the same lighting and adjust it according to your standard testing.

Do NOT stress this test. There is a +/- to it so it is all good. You will find how much CYA your pool needs to keep some of the FC in it all day.

I hope this helps

Kim

Hi Kimkats,
On the basis that the Standard was a "ground" for testing and was below 30 (say 15) and my pool CYA was 38, then using this as a compare my CYA should be atleast 53 possible more or less as it doesn't measure below 30. Is that what you were saying?

 

[kimkats]

That is my thought process. I would call your CYA 50 for Pool Math and such.

I have the standard and it shows as 40 for me. I really think it is how well our eyes see.

Kim

 

[buballodingo]

SO I had a 4ppm drop today versus a 2 ppm drop the day before and the day before that. Unsure what was different today? SO I have adjusted the SWG to 40% up 10% from the last few days to hopefully stabilise the drop. I have kept the SWG running at 8 hours simply because I like the circulation of water. I think I will test again only on the weekend and see what happens.

 

[needsajet]

That sounds good overall, but if it were me, I'd test each day cause it's near minimum now. After a little while, stretch it out to two days, three days, then twice a week at least during swimming season. If algae starts in the cover, or anywhere else, I'd want to know about it pretty fast. Three/four days right now I think is chancy.

Help me know where it stands now... you've been running 8 hours at 30%, and you had a 2 ppm FC drop in 24 hrs? From 6 ppm down to 4 ppm, right?

 

[buballodingo]

Hi Needsajet,
Last week or so is below:

	21/01/2017 20:46	10.5								80.78	-0.22	SWG 0%, only circulating water 6-10 AM & PM to drop FC. This is only a OCLT
	22/01/2017 5:07	9.5	0.5							78.00	-0.25	SWG 0%, only circulating water 6-10 AM & PM to drop FC. This is only a OCLT. OCLT passed.
	23/01/2017 18:52	11.5	0.5	7.6						82.22	-0.02	SWG 70% 6-10AM and 6-10PM.Skimmer/main drain valve set 75%/25%. CYA inconclusive so ignored, hard to get right
	25/01/2017 18:34	15.0		7.6							-0.02	SWG 70% 6-10AM and 6-10PM.Skimmer/main drain valve set 75%/25%. I dropped SWG to 60%
	27/01/2017 18:38	15.0									-0.02	SWG 60% 6-10AM and 6-10PM.Skimmer/main drain valve set 75%/25%.. I dropped SWG to 50%. CYA may be low test again in a week
	29/01/2017 17:34	13.0	1.0	7.6							-0.02	SWG 50% 6-10AM and 6-10PM.Skimmer/main drain valve set 75%/25%..
	30/01/2017 18:50	11.0					38				0.01	SWG 30% 6-10AM and 6-10PM.Skimmer/main drain valve set 75%/25%..I checked CYA against standard too and low. Got higher result from pool water
	31/01/2017 18:34	7.0	0.5								0.01	SWG 30% 6-10AM and 6-10PM.Skimmer/main drain valve set 75%/25%. IF BELOW 10 RAISE FC SWG TO 50%. To make up 2ppm loss per day at 30%

 

[needsajet]

My bad. I mis-read what you said, mate. Good level and progress and your records are great!

 

[buballodingo]

Couldnt help myself...I had to test the pool...its like an addiction.

	31/01/2017 18:34	7.0	0.5								0.01	SWG 30% 6-10AM and 6-10PM.Skimmer/main drain valve set 75%/25%. IF FELOW 10 RAISE FC SWG TO 50%. To make up 2ppm loss per day at 30%
	2/02/2017 19:28	7.0		7.4							-0.39	SWG 40% 6-10AM and 6-10PM.Skimmer/main drain valve set 75%/25%. Adjusted up 10% to cope with FC drop. FC maintained - 27 degress weather. Bbeta test for salt

Slight PH drop of 0.2 which I will monitor and it appears FC was maintained at 40%. Weather was 27 degrees outside so not as warm or as sunny as usual as it has been raining.

Some hot weather coming this weekend so will be interesting to see what happenns with my FC. I am tempted to put it back to 50% to cope the the hotter days as FC at 7 feels a bit low/risky to me?

 

[needsajet]

ahaha yeh, I thought you'd check it

FC at 7 ppm and 50/60 CYA would be more than enough ordinarily. The main difference for you is the submerged cover and being sure algae doesn't get established there again. Great to hear that you're pulling some water from the cover storage pit. I think you're fine where you are unless you see a big drop. Per TFPC guidelines, your minimum would be around 3, but I wouldn't go that low until the cover is proven to stay clean.

The other side of the story is that you could run 12/15 ppm FC and no one would notice, so there's room to tweak the SWC either way and observe the FC performance in your now clean water. You'll lose a bit more per day at higher levels, and less per day down closer to your "yet to be known" ideal level.

 

[buballodingo]

Hi Kimkats,
On the basis that the Standard was a "ground" for testing and was below 30 (say 15) and my pool CYA was 38, then using this as a compare my CYA should be atleast 53 possible more or less as it doesn't measure below 30. Is that what you were saying?

Measured CYA again today was at 38 to 40 again so consistent ....taking the above into account it means I am sitting at around 60. Have a pool party today and my FC dropped to 3.5 so will need to top up some chlorine --- lucky I checked...CC was at 0.5 so all good - it must be the heat? but still concerning that I can leave the pool for 2 days and I even raised the SWG to 40%.

 

[kimkats]

You would think you could leave it for 2 days. I don't have a SWG so don't know for sure but many talk about being able to set the SWG and call it good for a while.

I have to wonder if the cover and cover pit could be your "special helper" in eating your FC That is the one big thing different you have.

You might have to push your SWG up even more until you find what works for your hungry pool.

I wish your pool was more trouble free

Kim

 

[buballodingo]

Pit and cover ate really clean...may have low salt and the swg warning indicator may not be working...so what i assumed i was gaining from the swg could be less...working through that now

Sent from my SM-G928I using Tapatalk

 

[needsajet]

It's partly your water volume sensitivity. I think you'll be adjusting the SWC the least by running a bit on the high side.

Kim's point is well worth keeping front of mind. There's a constant risk from the cover because of the open slats which will have reduced water circulation vs. what happens in the pool. I personally think the pit will be OK now that you're drawing water from the drain in there, but the still water in the slats will not have fresh FC flowing in, other then when it opens and closes. So if there is a bit of algae, the FC will get consumed killing it, but if any algae is left after the FC is gone, it will flourish in there, especially when covering the pool and there's light getting in. I do think your pool is trouble free now, but I also think it's possible extra attention will be needed to keep it that way.

 

[buballodingo]

Im actually more confident and happier that I found out my salt was low or potentially low. If you recall you helped me with the mySWG calculator to see how much Chlorine I would generate per day based on my SWG:

Formula for SWG chlorine production
Description	Amount	Units
SWG model capacity	25	Grams/hour
Running time per day	8	Hours
% on LCD	40%	Bars on LCD, each bar = 10%
Pool volume	20724	Litres
PPM conversion	1000	Conversion
Production per day	3.86	PPM
Production salt Level	5000
Actual Salt level	2800
Actual Production Per Day	2.1617448

What the calculation did not consider is my salt level had to be 5000ppm for the SWG to generate for eg and as per the calculation above 3.86ppm, where I was only actually gaining 2.16ppm per day due to low salt.

Back in those days I was losing 6ppm FC every day and everyone thought I was still having algae problems. In fact I was only losing around half of that so the reason I am much more confident now. I added enough salt to get to 4000ppm and will test it tomorrow to check I have hit or am around that target. Then I will adjust the SWG to get the right balance, as to date my assumptions and calculations on FC gain has been incorrect and not enough to counter actual loss.

Will see how it goes.

But this could also mean I have an SWG problem. I am hoping that it means the warning light only is not working and it is still generating chlorine...I will look into ways of testing my SWG during the week to ensure it is doing what it is supposed to.

 

[buballodingo]

Feels like a big kick in the guts. Turned my pump on to circulate my water prior to testing. Error light came on...got it going. Unsure if I had the filter on last nigh and this morning. I added just over a litre of chlorine yesterday in preparation for a part...to get FC at 10 from 3 ish. Measure FC now and it is at 2. Not sure if it was from the pump being off, but sure hope it was. The SWG is defintely working. You can see the salt cell getting cloudier as I raised it 100% to get the chlorine level back up over night. Added more salt as I think I will just run it at 5000ppm now as per manufacturer recommendations till I get the pool running ok.

Could that massive drop be from bather load yesterday (7 kids and 2 adults for around 6 hours ) and potentially the filter pump error...ope so, otherwise im about ready to throw in the towel...kids want to swim now too...just gonna let them jump in it was 38 degrees to day.

 

[needsajet]

That is a kick up the clacker, but don't sweat it. Bather load is a huge impact and good that you added some extra FC to be prepared. Adding some more after isn't a bad idea either. You can also just flip the pump to "manual on" when swimming and back to "timer" when you're done swimming.

A rough rule of thumb is 4 grams of chlorine per person-hour. You had 54 person-hours, so that's around 200 grams of FC, or around 1.5 litres of 12.5% (or around 8 hrs of SWC time).

The most important thing is: "You're on it!"

Dropping to 2 ppm FC briefly isn't going to do any harm. It's still sanitary, but does need to be dealt with to prevent algae, and you're dealing with it. All good, mate.

 

[buballodingo]

Thanks needs...i had the filter running thecwhole time at 50%...will find out tomorrow when i test and hopefully its just the pump was off that made it worse. Good tip re bather load...will keep it in mind...but just need to have break from this testing...

Sent from my SM-G928I using Tapatalk

 

[Caco]

Hi buba
I havent got round to reading the last few pages but I can see that Needsajet and others have been helping you out
I can understand if you feel like you need a few days off testing, I know I would after all this time
You can just run your chlorine a little high for the next few days and enjoy swimming
You would probably be the only one to know that the FC was a bit high, the kids certainly wont notice

 

[needsajet]

Yeh, I hear ya! About all I can say is "It will get easier." (especially as the days get shorter and the water a bit cooler)

I do three SWC pools in the fam on a twice a week schedule. At the beginning for each one it was more like daily or every other day until I got them sorted. For these last two scorchers, I had to do an extra check on the 27,500 litre pool that gets major kid load. In that pool, the daily FC demand goes up and down like a .... ummm .... yo yo.

It will become routine over time, and believe it or not, you'll even get instincts sometimes when FC or acid additions will be more or less than the routine amount.