Starting resurfaced pool

[Kidney]

I forgot I have 4 trichlor chlorine tabs I could use in my old floater to get things started with chlorine and CYA at dusk. Should I bother to use them or should I just start using bleach and CYA?

[Watermom]

Sorry to be slow to reply. I've been out running errands all day. (Even Watermom has a life outside of this forum! )

Bleach is not going to affect your pH much. However, since you need chlorine, are fighting high pH and need CYA, a good choice for you would be to use dichlor. It will add the needed things and the acidity of it will lower your pH some. You actually might benefit from using our Super Simple Startup Recipe since this a new fill. Info about that can be found at this link: http://pool9.net/ssr/ (It is appropriate for any freshly filled pool -- not just Intex.)

I think you are going to find that a CYA of 25 is too low. It is simply too hard to keep chlorine in a pool at that level especially on hot sunny days and in Texas, you're going to have plenty of them. I would suggest at least 40-50 as a target.

If you decide that you don't want to use the 'recipe' but instead are going to use bleach and add CYA separately, every pound of stabilizer will add 10ppm of CYA. Also, in your pool, each quart of 8.25% bleach will add about 1.5ppm of chlorine and each 121-oz jug will add about 5.6ppm. Use those as a reference as you are figuring out how much to add.

Hope this helps.

[Kidney]

I fully understand the need to run errands Watermom ;-) No need to be sorry, and thank you for your help!

I am on day 5 following fill up so I am not sure I still qualify as a fresh fill and can use the Super Simple Startup Recipe. Dichlor sounds great and it looks like I could also use Leslie's Chlor Brite Granular (99% sodium dichloro-s-triazinetrione, right?) as I don't have a Sam's Club membership. Amazon would take too long to deliver. Leslie's is closed now so I think I will go ahead at dusk today and add 2 quarts of 8.25% bleach to remain in line with what the NPC instructions my installer provided suggest. I can get CYA tomorrow or start using dichlor tabs. Once I reach a sufficient CYA level, what do I do: start using bleach only?

As for CYA level, I used to have high readings by using trichlor tablets but I also had to empty the pool a couple of times to get things back on track. So I have no experience running lower levels (50 is low compared to what I was used to) and I don't know how fast FC disappears at that level. I was looking at 25ppm CYA only at first but was contemplating running at 30 after I found http://www.lincoln.ne.gov/city/healt...f/Cyanuric.pdf. This PDF states the CDC found CYA levels above 30ppm diminished "chlorine’s ability to inactivate the chlorine-resistant protozoan, cryptosporidium". Not sure the CDC still has this recommendation or not. This was a 2007 study...

[Watermom]

Have you only used bleach thus far? If you have not yet added any CYA, you could still follow the SS Recipe. It is just a simple way to build up CYA using Dichlor while adding chlorine. (Does the Leslie's Dichlor say 55 or 56% chlorine? If so, then it is fine to use.) (By the way, dichlor is granular, not tabs.)

You are right that if you do decide to use dichlor, when you get your CYA to the level you want, then you just switch to using bleach so your CYA doesn't get too high.
If you follow the chlorine levels in the chart at this link, your pool will be properly sanitized and will also keep algae at bay. http://pool9.net/cl-cya/

As far as Amazon goes, have you ever heard of Amazon Prime? For $99 per year, you get free shipping on products they stock and also delivery within two days. If you shop a lot at Amazon, you'll get your money's worth. I know I save way more on the free shipping costs in a year than my $99.

[PoolDoc]

Couple of quick points:

1. If the your finish product company wants you to wait on the chlorine find, and add, some polyquat ASAP: http://pool9.net/polyquat/ I'd recommend ordering a quart from Amazon, but then seeing if you can find some locally, sooner. You do NOT want your pool to turn green. Just save whatever polyquat you don't use -- it lasts indefinitely -- and use it to 'keep' your pool when you go on vacation.

2. Kent Williams' article on CYA frankly pi##'s me off. It's about time I wrote a rebuttal entitled something like "Kent William's Cyanuric Acid theories: merely ignorant or actually fraudulent?". His background is as an employee for Stranco, who made very expensive, very high-end commercial pool chemistry controllers. The problem is, these controllers work very badly on pools with CYA present. Many years ago, I talked with an Arizona parks and rec director who was FURIOUS at having bought a number of those units for $10,000's . . . only to discover that they wouldn't work on his outdoor stabilized pools.

The "Benefactor or Bomb" article reflects earlier efforts by Stranco to get rid of stabilizer in commercial pools, NOT because it was bad for those pools, but because it was bad for their product. By blaming CYA, they could deflect blame from their over-priced and under-functioning controllers.

The fact is, without CYA, it's almost impossible to keep commercial pools safe. With clear water under full sun most large modern pools, with side wall inlets, do not have adequate circulation to make sure the interior areas of the pools remain chlorinated when there's a heavy bather load. Ironically, many old pools built in the 60's and earlier, have floor inlets scattered around the pool that made it practical, if not very efficient, to keep unstabilized pools sanitary.

Anyhow, the "CYA, B or B" article is based on a misunderstanding of CYA chemistry -- but since the purpose of those theories was apparently to protect Stranco controller sales, why bother with getting the chemistry right?

[Kidney]

Watermom: I added 2 quarts of 8.25% bleach at dusk tonight only. No CYA yet. (I am really curious to do my first FC test tomorrow morning and see what it reads....). I have so far followed the National Plasterers Council start up card at https://npc.memberclicks.net/assets/...nt-rev3.09.pdf as per my Pebble Tech installer's instructions. This start up card asks to "adjust Cyanuric acid levels to 30 to 50 ppm based on the primary sanitizer of the pool". Dichlor is not excluded but before your post I was planning tomorrow to raise CYA to 30 at the least in one row (not sure if that's allowed by the Leslie's conditioner. i.e 100% CYA, I was going to use). My installer recommended 25ppm in anticipation that its clients will use trichlor tablets and do not need high initial levels of CYA (but I don't plan on using trichlor). Also I don't know if Leslie's Chlor Brite is 55-56% available chlorine: does that mean that if it is not 55-56% (i.e. dihydrate I assume) but 62-63% (anhydrous), I should not use Leslie's product? (BTW, I know about Amazon Prime, I just haven't used this service yet.)

PoolDoc:
1. Pebble Tech just say not to chlorinate water that has not been filtered and is not within acceptable ranges for pH and TA. As my water has been filtered and is within acceptable ranges (with pH fluctuating some but in range today), I added bleach. As I mentioned above the National Plasterers Council directions I follow ask for chlorine to be added 3 days after fill. As I now have some chlorine in the pool and will be able to decide this Tuesday morning whether to keep using bleach and added CYA or more simply dichlor (assuming Leslie's is 55-56% AC), I do not think I need to add polyquat, correct? (Today and since day 1, the pool was sparkling clear.) Would you have a link to a page discussing using polyquat (or other techniques) when going on vacation?
2. Thank you for shiming in on the reference to Kent William's article. That did seem really contrary to common wisdom but what about the CDC's findings regarding diminished "chlorine’s ability to inactivate the chlorine-resistant protozoan, cryptosporidium": should we worry about this at all? (I must admit I haven't done any research yet about protozoan cryptosporidium but it does remind me of a parasite some people suffer from after bathing in local water reservoirs but I may be wrong...)

Let me express my gratitude for your very helpful answers!!!

[PoolDoc]

Adding CYA reduces the percentage of chlorine that is active at any given time. That's bad, if you try to follow the 1 - 3 ppm recommended levels . . . but we don't!

In fact your target chlorine level should be 5 - 10% of your CYA level. If you operate that way, you'll have a fairly constant amount of ACTIVE chlorine present.

BUT, there's a huge advantage to higher levels of CYA *if* you follow our cl-cya chart: http://pool9.net/cl-cya/ . You can have FAR more chlorine in reserve, ready to almost instantly replace the ACTIVE chlorine, if it gets used up.

[Kidney]

This morning at 9:45am on a bright sunny Texan day:

TC 0.1 (using K1000), FC 0.8 (using K2006C after adding a lot of powder), CC 0.2
pH 7.8 (or 7.9)
TA 80
CH 160
Water temp 79
SI 0.05

Not sure I am doing the right thing yet with the FC/CC test in the K2006C. Very hard to read at these low levels.

pH is back up, TA is perfect: should I add dichlor and wait 3 to 5 hours before retesting in the hope pH dropped, or more drastically lower pH with muriatic acid or even raise TA with baking soda then lower pH with muriatic? I discovered http://www.poolsolutions.com/gd/lowe...p-by-step.html after having followed my installer's instructions to lower TA (initially reading 120) but now my pH is bouncing around and TA is in range but no longer high so not sure I can or should follow directions at this link.

I will make a run to Leslie's to get dichlor if it is 55-56% available chlorine. Should I use bleach and CYA if the dichlor I found is 62-63% available chlorine?

PoolDoc: the best guess chart is great, your rule "your target chlorine level should be 5 - 10% of your CYA level" is even easier to remember! Thank you!

Watermom: regarding the Super Simple Startup Recipe, I assume I skip adding "borax in equal quantities as dichlor" since my pH is so high, correct?

[Kidney]

Over the past week or so, I have used seven 1lb bags of dichlor and things are looking pretty sweet around here. Chemicals are in balance but I have a question.

My CYA is now in the neighborhood of 30ppm and my TC at 3ppm (or 4) after I add dichlor at dusk stays there until the morning and drops to 1ppm after a long day of Texas sun.

Can I expect TC to drop less if I raise my CYA to 40ppm as Watermom recommended and even less if I raise it to 50ppm? (Right now with CYA at 30ppm, I believe I would need to add ~6 cups of 8.25% liquid bleach every day to bring TC back to 3ppm at dusk on an ongoing basis and it would obviously be great to have to use less bleach.)

[PoolDoc]

As CYA increases, so does the half-life of chlorine in the pool. With CYA = 0, the half-life in clear shallow water is as little as 15 minutes!

However, the effective life of chlorine seems to go up as CYA increases, even when you maintain a constant available unstabilized chlorine fraction. For example, a pool with CYA = 20 pm and FC = 1 ppm has approximately the same available unstabilized chlorine as a pool with CYA = 200 ppm and FC = 10 ppm. But reportedly it takes MORE chlorine to maintain the first pool at 1 ppm, than it does the second pool at 10 ppm, assuming equal gallons, loads, sunlight, etc.

That's really something I need to experiment with.