Confused with keeping Fc at the right levels

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I think I'm confused as to what my target is now. I think my fc loss is due to the sun and no cya. I know I'm slowly raising it because I don't want to go crazy cya. I still eventually want to be at 70 right? with an fc of 3-5?

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Yes, the target will be 70 CYA. And also yes, if you want to save some money, you can return the liquid stabilizer, the dichlor and the dry acid. Just use pool math to work out what you need.
 
Ok that's what I thought... slowly but surely! Thank you! You said I only need to run the filter an hour after adding Stabilizer correct? I kept my kids out of it yesterday due to the cloudiness. So was hoping to add it this morning so they can swim later. Unless it's too cloudy still :/ I just pour it in by the return I know... but the instructions on bottle say to then rinse bottle and put into skimmer.. that's ok right? Thank you again!!!

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Okie dokie gallon of liquid stabilizer was added about an hour ago. How long do you wait to retest for CYA with liquid stabilizer. I am still filtering but my water is still cloudy. My Fc was 9.5 so I am sure some will get used up today since the sun is beating down on my pool. I will definitely need to add more stabilizer to get to 70 but I like doing it slow. Helps me not to go too far , especially since I am new to this.

Should I run all the tests again soon, just to see where I am at?

Questions for swimming purpose...I have seen a lot of people wonder (as am I) because it's confusing. I get if fc is low , people probably shouldn't swim.

My cya is 30 and fc 9.5 .... Is that swimmable? Is it swimmable after you introduce most chemicals (dry acid, stabilizer, etc)? My pool water is still cloudy but its not algae since I didn't lose fc. I can see the bottom ,but its murky. Do I keep the kids out of it? I don't want anyone to get sick.
 
you can swim in up to your shock level for your CYA, so if your at 40 now that is FC16, so no problem swimming.. But, it needs to be clear, you want to be able to see all the kids in the pool...

You can add DE to your sand filter to clear it out faster but your pressure will also rise fast and need to be backwashed sooner.. to do this you

add 1 cup DE slowly in your skimmer until your PSI on the filter raises 1 PSI then stop... watch your pressure and if it goes 25% backwash

:) Amazon.com : Diatomaceous Earth Pool Filter D.E. 25 LBS. : Swimming Pool De Filters : Patio, Lawn Garden
 
Thanks cowboycasey! Its slowly clearing up I think. I think the sprinkler people put a lot of dirt in my pool :( I can see the bottom..I can see the two drains fine, it's just cloudy. I just wanted to make sure that didn't mean it was contaminated.

I have to vacuum again but will do that tonight when it isn't so hot. I have brushed it a few times . Do I continuously filter? Im going to brush again and then vacuum tonight. Questions:

1) When should I retest everything ?

2) How long after liquid stabilizer will it show up in my test? If my pool math is correct, it should put 15 ppm of cya in so I should be up to 45.

3) I am not sure if I have my pool size correct. Someone mentioned they have 26900 20 x 40 pool but have an 8 foot deep end. The pool math says mine should be 26900 and I have a 6 foot deep end. The pool store told me I was 28000. It was suggested to go by 25000 gallons on the forum because everyone overestimates the size of the pool . I guess I will know when the cya goes up?
 
the easiest way to know the size is free chlorine...

test FC (say 6FC)
using poolmath add to 8fc

test 30 minutes later, is it 7, 8, or 9 FC

adjust gallons up or down

doing it this way use the 25ml tube and go to .2 so it would be 6.2fc and 8.2

I would retest everything tonight and see where you are, the liquid CYA can be read an hour later
 

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Ok here are my latest numbers:

FC: 6 (was 9.5 and passed overnight FC loss.)
CC: possibly .5. Before any drops it looked fairly clear but had a slight pink tinge. When I added the drop it went away ...so thats what I am going with
TA: 130
PH: 7.5-7.8 again hard for me with the colors. It looked right in between honestly
CH: 200
CYA: It was at the 50 mark before it went cloudy.. Question. ..sometimes it is hard to see when I first squirt it in but after a second I can see the dot. At 50 I really struggled. I am not good at this cya...lol
 
6 is your target so your good there, always keep it above 4
7.5/7.8 are both good just when it turns red at 8 drop it down, it will go up kind of fast from your TA being 130 but the MA will also drop the TA down..

CYA is the hardest, pout it back and forth 10 or 15 times and get a good average and go with that :)
 
Yes, the 6 ppm FC is a tad on the high side, but will not cause any problems of any kind. No swimmers will find it high; it's just a touch higher than it needs to be.

While you're at 50 ppm CYA, your bare minimum with SWG is 2.5 ppm FC and your target is 3.5 ppm FC (call it 4 for round numbers). I think you're doing fine on the CYA test. Some people prefer just to glance at it to know the right point. If you stare hard you'll see it, but the glance method seems about right for many people.

So, next steps... for optimum SWG performance, we can raise CYA some more. On the other hand, if you have any concerns that the water may yet have algae in it, it's better to keep it at 50 for a little while. Everything is sounding fine, so that's up to you.

if you want to raise the CYA a bit, you can use up the packets of dichlor, one per day. Or you can leave those for future use, and add some more stabilizer. Again, your call, I think you have a very good sense of everything.

Eventually of course, you'll have your CYA at 70-80 ppm for best performance with the SWG.
 
ok great. Ya I'm sure it's 6 because it's starting to burn off from the sun... Since I passed the fc loss, no algae right ?

Ok so I can raise my cya either way. My confusion is maintaining the fc. The Cya helps with that so at some point when Cya is 70, the fc should stay in better? With a swg, I shouldn't always have to manually add chlorine.. it should maintain it? I have the boost on my swg and I was told that "shocks it". But now I realize how can it because it doesn't know my cya. Boost would be good to add some extra chlorine in if I had alot if swimmers?

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Yep, you're really getting it all. And yes, we're assuming algae is gone because of the passed OCLT.

The FC daily extinction will be whatever is needed to eliminate contamination plus whatever is lost to the UV radiation from sunlight. CYA makes FC last longer by protecting most of the FC by holding it in a buffer system, which reduces the speed that FC is lost to sunlight. As the harsh part (the active part) of chlorine gets used up, the CYA "releases" more chlorine to become active chlorine which can eliminate contamination. At any given time, there is very little "harsh" or active chlorine in the water, because the CYA essentially "holds" FC in reserve, to be available as needed. The more CYA there is, the more the FC is protected, yes.

Your SWG makes fresh chlorine which becomes part of the buffer system, and replaces the chlorine that gets used up, whether it is lost to sun, or used for decontamination. So now you'll dial in your SWG to cover the daily losses of FC. The daily losses might average 2-3 ppm FC per day, so the SWG has to make approximately that amount. On a super hot heavy swim day with lots of fun in the pool, the loss will be higher, maybe even 4 ppm FC. A cloudy cool day, with no one swimming and super clean water, the loss might be only 1 ppm FC. You'll see this in your testing if you test daily for a while.

Say we set the SWG to make 2.5 ppm FC per day. If you have an easy day, and only 1.5 PPM FC is used, your pool FC will rise by 1.0 ppm FC. If you have a pool party, and it's hot and sunny, and it takes 3.0 ppm FC that day, your pool FC will drop by 0.5 ppm FC.

Boost simply turns the SWG to 100% and possibly a 24 hour period, or steady until midnight, or something like that. I don't know your SWG or controller well enough to say. But I can say it is not shocking. It might add a few extra ppm FC, nothing like shocking. I use my boost for about 12 hours for a party, and it adds about 2 ppm FC extra, to absorb the extra bather load. And yes, you've got it. It is dumb and just pumps out some extra chlorine.
 
wow thanks for thay explanation. I actually understand that. I think I need to learn my system because I don't know how to program it to make it make a certain amount. We have it at 75% running 4 hours at night and 4 hours in the morning. Now we have had some downpours the past couple of days... which may contribute to a lower fc? My fc is now at 1.5.. with my cya at 50. We are going to use the bags of dichlor like you suggested and raise the cya. My pH is creeping up again ? It's almost at 8.2.

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Be sure to keep your FC 2.5 and up. The 2.5 needs to be a bare minimum. Also keep your pH between 7.2 and 7.8 which is also important. Pool Math is your best friend and will tell you the effect of each bag of dichlor. There's a spot at the bottom called Effects of Adding Chemicals
 
The upward creep of pH is quite normal and should be managed with muriatic acid (MA) additions. Over time, the MA additions will bring your TA down, and then less frequent MA additions will be needed. You can drive TA down faster if you want to, but it will come down on its own. Each bag of dichlor will bring it down by about 0.1 of a pH unit, which isn't enough to bring it down into range, so that's why you'll need the MA.

If you want to bring TA down faster, you can follow this procedure Pool School - Lower Total Alkalinity
 
Thanks needsajet! I did add the bag of dichlor and what was left of my dry acid. That is exactly what I was wondering.. if it's normal. Good to know. I need to get some MA today. My pool is still slightly cloudy (I'm assuming from pH?) and I'm still vacuuming dirt out. I Had it almost perfect until the sprinklers people ugh.

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