New to this all

phonedave

Well-known member
May 30, 2012
647
Montville NJ
#1
Hi all

This new house came with a new pool and I just want to make sure I am on the right path

27' round above ground pool 47" deep - about 17,000 gal
Hayward DE fileter - model EC-40 with a 1 HP pump (supposedly 40 GPM)

I opened the pool and the water was not too bad. Hazy, some leaves, but no green
I set up the filter, skimmed the leaves out, dumped in the shock that came with the house, and let the filter run
When it got to the point where the filter had to be bumped after an hour, I changed the DE

I had Tri-chlor tabs in a floater for 3 days, and vaccumed daily

I tested and mY TC was 2.0, read this site and learned better, removed the tabs, and added bleach (144 oz 2 days ago and 48 oz last night) asd recommended by tests and the calculator

The water is now clear and I have the following readings

CL: 2.5
Ph: 7.2
AK: 100
Hardness: 280
CYK: 50

The water is clear, but I keep getting dirt in indentations in the bottom (it is not DE, it looks browner)

So, just to make sure I am on the right page here, I should do the following:

1) Add 60 oz of Boarx to bring up the Ph (as per the calculator)
2) Monitor Cl ever day, and add bleach in the evening as required to keep the CL at 2.5 (it appears to be all free CL, as there is no color change when measuring)
3) Vaccuming or running the automatic cleaner will eventualy remove all of the dirt
4) Run the filter for 7 hours per day, in order to turn to pool over once per day (is there a better time to do this - I have a timer)

So my take is, the pool is now safe for swimming, it just needs some minor Ph tweeking and then upkeep.

I guess if the TC drops a lot, or I see evidence of a difference in FC and TC, then it's time to shock

Thanks for all your help

-dave
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
41,197
Tucson, AZ
#3
No need to adjust pH.

Is the CYK really supposed to be CYA? If so, according to Chlorine CYA Chart for a CYA of 50ppm, you should NEVER let your FC below 4ppm

You can do the Overnight FC Loss Test to find out if your have anything living that would require you to follow the Shocking Your Pool process (NOT a 1 time addition of some random chemical).

What was the "sh**k" that you added? We use that word as a verb and not a noun.

You certainly should stop using tablets if your CYA is 50ppm. The fear is that some of it may not be showing up in the test yet and could go higher.

EDIT: Just have to add that you would be best served by getting on of the test kits we recommend as linked to in my signature.
 

frogabog

LifeTime Supporter
Jul 16, 2010
1,578
Portland, Oregon
#4
jblizzle said:
Is the CYK really supposed to be CYA? If so, according to Chlorine CYA Chart for a CYA of 50ppm, you should NEVER let your FC below 4ppm

EDIT: Just have to add that you would be best served by getting on of the test kits we recommend as linked to in my signature.
Just wanted to emphasize these two very valid points. You're on the right track, but that 2.5ppm CL is too low for your CYA level. Additionally, you need to adjust your thinking about chlorine levels to understand that there's a minimum and a maximum range and how it applies to daily dosing. The range for 50ppm CYA is 3-7ppm FC. You're going to lose 2-4ppm per day to bather load and sunshine. This means you'll have to start each day at 7ppm so that you never fall below 3ppm. We suggest to dose to max every evening after the sun is off the water and swimming is done. If the pool is balanced and nothing wonky, you won't lose chlorine overnight so the next morning you start with a full max FC level of 7ppm. It will be in the 3-5ppm range at the day's end. Every day, day in, day out.

You won't know what you lose each day till you can test morning and evening for a few typical sunny/swimmy days. After a while you'll know how much you need to add every evening and won't need to test every night but at first, testing before dosing at night is the only way to know.
 

phonedave

Well-known member
May 30, 2012
647
Montville NJ
#5
jblizzle said:
No need to adjust pH.

Is the CYK really supposed to be CYA? If so, according to Chlorine CYA Chart for a CYA of 50ppm, you should NEVER let your FC below 4ppm

Yeah, my typo - Thats CYA not CYK. I had read that page a number of times. I get the idea that CYA ties up CL so you need more. But everwhere else I look "they" say the proper CL level is 2.0 and never, never, never, never, let it get above 4.0 (unless shocking), yet this site says never let it get BELOW 4.0 (or even higher at higher levels of CYA). Are we measuring the same thing here? It just seems odd to me that after reading a bunch of other information, this is the only site where I see the recommended CL levels are so high. Everything else on this site seems well though out and makes sense. Maybe it's because I am an engineer, but I need to know the why.

You can do the Overnight FC Loss Test to find out if your have anything living that would require you to follow the Shocking Your Pool process (NOT a 1 time addition of some random chemical).
In order to do that I need to get a titrating test kit (as you said below) I will say, that using the HTH OTO kit that I have, there appears to be no loss of FC

What was the "sh**k" that you added? We use that word as a verb and not a noun.
Granulated CL

You certainly should stop using tablets if your CYA is 50ppm. The fear is that some of it may not be showing up in the test yet and could go higher.
That's what I figured. I really don't feel like having to drain and refill. I get the feeling the previous owner used a lot of tabs, as they were left over from him. When I opened, he had drained the pool to below the return, so I had to refill a bit. Even after that the CYA was 50, so it must have been a bit higher to begin with. I have also tested the CYA twice and it seems pretty stable at 50


EDIT: Just have to add that you would be best served by getting on of the test kits we recommend as linked to in my signature.
[/quote]

Yep, working on it.

Thanks

-dave
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
41,197
Tucson, AZ
#6
Which granulated CL? Could be dichlor / trichlor / cal-hypo?

The unbelievable thing is that MOST pool stores do NOT understand the CYA/FC relationship ... or they ignore it to seel more product.

The 2-4ppm recommendation you mention is really for pools with ZERO CYA (public pools and indoor pools often fall into this category).

The is a lot of science that backs this up ... much of it in posts by Chem Geek. You can probably find more information than you care about in The Deep End or Chemistry 201 forums.

Check out this thread for example:
how-much-chlorine-is-too-much-t45170.html
In fact the first post by Chem Geek explains the 4ppm max most people mention.
 

phonedave

Well-known member
May 30, 2012
647
Montville NJ
#7
jblizzle said:
Which granulated CL? Could be dichlor / trichlor / cal-hypo?

The unbelievable thing is that MOST pool stores do NOT understand the CYA/FC relationship ... or they ignore it to seel more product.

The 2-4ppm recommendation you mention is really for pools with ZERO CYA (public pools and indoor pools often fall into this category).

The is a lot of science that backs this up ... much of it in posts by Chem Geek. You can probably find more information than you care about in The Deep End or Chemistry 201 forums.

Check out this thread for example:
how-much-chlorine-is-too-much-t45170.html
In fact the first post by Chem Geek explains the 4ppm max most people mention.

OK, so FC is not really "free" is CYA is present.

I was under the impression that CYA "protected" the CL from UV degradation, but did not "hold it up"

Now I am understanding that the 50 ppm of CYA in my pool has "captured" roughly 2 to 3 ppm of CL and never lets it go, that is why I need 4 to 8 ppm of CL. The "captured" part of the FC does not interact with pathogens, bathing suit fabric, or hair, so it does not count when it comes to CL levels.

OK, so if that is the case, then what benefit exactly does CYA have? If it protects CL by tying it up so much that it is basiciy useless, wouldn't it be better to have none, and just let the sun break down what CL you have, but have it all avaialble for use? Or does the CYA benefit outweigh how much CL is tied up at lower concentrations?

Thanks

-dave
 

frogabog

LifeTime Supporter
Jul 16, 2010
1,578
Portland, Oregon
#8
phonedave said:
I had read that page a number of times. I get the idea that CYA ties up CL so you need more. But everwhere else I look "they" say the proper CL level is 2.0 and never, never, never, never, let it get above 4.0 (unless shocking), yet this site says never let it get BELOW 4.0 (or even higher at higher levels of CYA). Are we measuring the same thing here? It just seems odd to me that after reading a bunch of other information, this is the only site where I see the recommended CL levels are so high. Everything else on this site seems well though out and makes sense. Maybe it's because I am an engineer, but I need to know the why.
The reasons behind this are forever questioned, debated, and baffled over around here. However, our pools are sparkly, clear, clean, fresh, and inexpensive to maintain. We don't add anything to the pool that it doesn't need, and we know how it tends to behave. Our pools don't typically go green or show combined chlorine, and if they do... we fix em up without stress, usually within hours because we catch it before any visual or olfactory signs appear (testing with the proper tools).

I don't know how many thousands of forum members there are right now, but there's a lot of us and not one person who has followed the advice here has failed. Any failures, didn't actually follow the advice. It just is fact.

Bottom line answer... the information you find elsewhere is almost always from a commercial source. The source often sells pool chemicals. Many of us are of the opinion that they like when your pool is icky so they can sell you lots and lots of weird stuff that won't work... so they can then sell you more expensive weird stuff that you arbitrarily dump into your pool without testing or knowing anything about. So they can then sell you more stuff... and so on. People can spend thousands of dollars a season on pool chemicals all the while the pool store is telling you to just come in and they'll test the water with their fancy computer (seems accurate, but it rarely is), and then dump in pounds of this, and pounds of that... and wait. They'll also claim that you really don't need your own test kit, but if you insist... "Here's a kit that only tests up to 5ppm and doesn't test TC. Don't worry, it's fine!" A pool store that doesn't carry a FAS-DPD test kit is surely trying to hide something from you... for whatever reason, I think monetary.

Read pool school again. Read ChemGeek's information and posts, look at the CYA=>CL information... it's very well researched and documented. Look at our sparkly crystal clear stress free pools that leave us so much extra time that we can come here and post to help people. Look at walmart or other grocery stores during pool season... do they have an adequate supply of bleach or is it inexplicably low?

You'll figure out the best why answer for you as you get normalized with BBB all on your own. Promise :~}
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
41,197
Tucson, AZ
#9
I am no expert, but here is what I think I understand.

With 0 CYA, the chlorine will be gone from the sun before it has a chance to attack anything.

It also does not exactly hold the FC continuously, as the FC is used, the CYA releases more that is then available to attack things.

You would end up having to add way more FC to a pool with zero FC as you are fighting the sun and the organics, while with the CYA there is some FC "held in reserve and protected from the sun" that can be used against the organics when the need arises.

Based on ChemGeeks posts, the key is the Active Chlorine level ... but I do not fully understand it, as I have not tried to understand it :) ... just believe it works.
 

frogabog

LifeTime Supporter
Jul 16, 2010
1,578
Portland, Oregon
#10
phonedave said:
OK, so FC is not really "free" is CYA is present.

I was under the impression that CYA "protected" the CL from UV degradation, but did not "hold it up"
It protects it only until you reach the protected level. Below that, it's not protected any more and will be consumed by organics.

Now I am understanding that the 50 ppm of CYA in my pool has "captured" roughly 2 to 3 ppm of CL and never lets it go, that is why I need 4 to 8 ppm of CL. The "captured" part of the FC does not interact with pathogens, bathing suit fabric, or hair, so it does not count when it comes to CL levels.
Correct, and incorrect. You'll lose less CL each day with CYA, it's not only protecting some PPM's, it's buffering all of the CL so that it doesn't just completely disappear every day. It also allows you to have higher levels without adverse affects on your person, clothing, pool, and equipment. Without CYA, chlorine will EAT anything it comes in contact with (check out indoor pool equipment, piping, and anything metal in the facility, corrosion is often apparent)

OK, so if that is the case, then what benefit exactly does CYA have? If it protects CL by tying it up so much that it is basiciy useless, wouldn't it be better to have none, and just let the sun break down what CL you have, but have it all avaialble for use? Or does the CYA benefit outweigh how much CL is tied up at lower concentrations?
It's not useless, it holds it in reserve so to speak, although below the minimum for your CYA level, it is rapidly consumed and algae can begin to grow. As opposed to 0 chlorine when algae WILL begin to grow if the sun is out at all. Indoor pools don't need CYA although some private pool owners will maintain around 20ppm anyway. The sun will eat your chlorine to 0 rapidly without it, well before you manage to catch it and re-dose.
 

phonedave

Well-known member
May 30, 2012
647
Montville NJ
#11
frogabog said:
[quote="

Now I am understanding that the 50 ppm of CYA in my pool has "captured" roughly 2 to 3 ppm of CL and never lets it go, that is why I need 4 to 8 ppm of CL. The "captured" part of the FC does not interact with pathogens, bathing suit fabric, or hair, so it does not count when it comes to CL levels.
Correct, and incorrect. You'll lose less CL each day with CYA, it's not only protecting some PPM's, it's buffering all of the CL so that it doesn't just completely disappear every day. It also allows you to have higher levels without adverse affects on your person, clothing, pool, and equipment. Without CYA, chlorine will EAT anything it comes in contact with (check out indoor pool equipment, piping, and anything metal in the facility, corrosion is often apparent)

Ah, that makes sense now. It is a buffer. I well know the corrosive properties of Cl

So why the big bugaboo about a level of 4.0? I know pool companies want to sell chemicals, but they could sell even more if they told yountomhave your CL levels higher. But then most people would add tri or dichlor, thus raising their CYA, requiring more CL. Quite he slippery slope.

I did add enough bleach to hit 5.0 tonight and ordered a test kit, so we will see what the future holds


Thanks

-dave
 

frogabog

LifeTime Supporter
Jul 16, 2010
1,578
Portland, Oregon
#12
I don't think they make big money on trichlor. It's shock and algae remover, clarifier, floc, green to blue products, non-chlorine shock, and this and that whatnot where they make the big bux. Ever seen the price of one of those tiny bottles of..."snake oil" they sell?

I really like the prices on small bottles of alkalinity increaser and pH up. Compare to the price of a box of baking soda and 20/20 Mule Team... ha! They're making BIG BUX on those ones.