Switched from Cal Hypo to Bleach

[Jakebear]

We finally finished making the conversion to your BBB method and have now been using Clorox Ultra 6% for 2 weeks.

Today while swimming we noticed a yellow/brown stain from the water line down on the steps and the skimmer boxes, also the skimmer baskets are no longer white. This stain was not there before we changed to bleach!!:mad:

Before finding this forum, we have always used Cal Hypo and pucks. We have always used our well water to top off due to evaporation or replace splash-out. The CYA has been creeping up from the pucks (as expected) so we quit using those about two months ago, and have been draining and replacing 500 to 1000 gallons every day or two to try work the CYA level down. The only real change is the bleach.

Below is the latest results:

Water Temp 87
pH 7.4 by titration
FC 6.0 ppm (FAS-DPD)
TC 6.0 ppm (FAS-DPD)
CC 0 ppm (FAS-DPD)
TA 80 ppm (by titration)
CH 250 ppm (by titration)
Phosphates <100 ppm
CYA = 55
Water is crystal clear:)

Added 120 oz Bleach this evening to bring FC back up to 8 ppm per Ben's BGC.

Finally ---- the question ---- What to do about the stain --- We really do not want to go back to Cal Hypo!!:(

[MaryLee]

It's probably mineral staining. Take a vitamin C tablet and put it on the stain for a few seconds and see it the stain goes away. If it does then you'll need to treat the water with ascorbic acid and a metal sequesterant. Check out all the info on the "metals" board.

[SUNNYDAYS]

For the white parts on your pool like the the steps and the skimmer box you may want to see if a little scrubbing with a Mr Clean magic eraser with help. I fine the need to do the steps and the skimmer box about once a month.

[DavidD]

Rest assured, It's not the bleach! There is now difference between the bleach and pucks except the bleach is higher in PH and has no CYA. As previously posted, sounds like minerals. At a higher PH, they will drop out but your PH seems perfect.

Dave

[Jakebear]

I've read over and over ---- Bleach is Bleach --- Chlorine is Chlorine and I accept most of that. :confused:

This is NOT an new pool --- We have had this pool 4 years and used Cal Hypo since it was new --- NO STAIN --- 2 weeks into usiing Sodium Hypochlorite and we have stains ---- There has to be a correlation to the reaction or chemical composition of the Sodium Hypochlorite ----- and a preventative measure.

I'm really more concerned with that aspect than I am with the stain which is why I posted to this forum instead of stains etc.

EDIT: Also the pH has been stable with no muriatic being necessary

[waste]

Jakebear, while I may not be the 'go to' person for this on the forum, a possible cause suggests itself. #1, have you ever noticed the same thing on your return jets, before the changeover? (esp the inside of the 'eyeballs'). [I'll assume a 'yes' answer and continue]. You said that "the only real change is the bleach", I beg to differ, another change is that you have been replacing 500 - 1000 gal every other day with well water. What I suspect is that you have a small amount of metal in your well water, small enough to have gone unnoticed with just regular 'top-offs' in the past and now you have increased the 'normal' amount in your pool by purposly increasing the concentration of well water in your pool.
With that said, there is a difference between the different types of chlorine routinely applied to a swimming pool; the concentration and delivery method. I don't know how you've added the dichlor and cal hypo in the past, but I think that it never came in close (concentrated) contact with the areas you now find to be staining. Bleach, on the other hand is usually poured directly into the pool, and I know that when I add it, I pay extra attention to the returns, stairs and suction areas - if you do the same, you have a 'plug' of highly chlorinated water in these areas and high chlorine will precipitate the metal out of the water.
But you asked for a solution:
Take some tap water down to a pool store and have it tested for metals, I truely think you'll find some. If you do have metals in the fill water, always add a sequesterant before adding the fill water (please see the 'stains and metals' section for more expertise advice). I may be way off, but I've given you the best that I can - Welcome to the forum!! - Waste

[Jakebear]

Hi Waste,

Thanks for the observations.
Let me address the points one at a time.
1. I have regularly removed the eyeballs in order to reposition the direction of flow (they are tight so they have to be disassembled to change. There has never been any noticeable stain or deposit seen there.
2. When we got the pool installed 4 years ago the pool company shorted us about 4000 gallons on the initial fill and we used the well to finish that fill. Since then we have regularly added thousands of gallons of water from the well every year to replace splash out and evaporation. The pool holds about 500 gallons to the inch so it has been easy to keep track of how much has been added.
3. As mentioned in the initial post we discontinued using pucks, on 6-24-06 to be exact (I keep very careful records in the form of an Excel Spreadsheet – every test – every treatment and setting). On the July 1, 2006 we started using Cal Hypo granules at the rate of 12 oz being equal to 1 gal bleach – in conjunction with Michael's bleach calculator to determine the dose. We did this until we discovered (with the help of y’all on this forum) that the Cal Hypo was causing the cloudiness that would not go away (see my posts back around 2 weeks ago). We took Carl’s advise and quit with the Cal Hypo and switched to bleach. The pool cleared immediately and all has been good until we noticed the stain yesterday.
4. I have taken samples to be analyzed but not to the pool store. They once told me I had CYA in the well water (another long story that’s 2 years old). To make a long story short I don’t trust them ---- period. I was looking at a water softener a while back and was told I didn’t need one and there was very little iron in the water. That was a while ago so maybe things have changed.

Lastly --- some of the other comments and posts in the “stain” section recommend using Ascorbic Acid. The instructions on the container I got says to lower the free Chlorine to between 1 and 2 ppm before using. Now with the CYA above 50 I hesitate to do that either.

I guess you could say we’re caught between the devil and the deep!!!

[waste]

Jake, HA! I was right on at least 2 things - I'm not the 'go to'guy here and, as I said, I may be way off! So there! ;)
Sorry, I really thought I had a good possible solution, unfortunately, your pool doesn't agree with, an otherwise excellent, assesment. I'll keep my eye on this and if none of the real 'go to' guys answer, I'll pm them and try to get you their oppinion. As I said, I gave it my best, good luck with finding the cause and solution.

[waste]

Jakebear, let me take one more stab at this before I call in the pros. Are these areas gritty, feels almost like sand? If so, you've calcified your pool (aka scale), and will need to adjust the pH and alk to alieviate the problem (though a look at your numbers scaling doesn't fit ).
You can use the ascorbic acid to test for metal stains without having to treat the whole pool - place a big ol' pinch in a stocking and rub at a small portion of the stain for a minute, if it lightens then the stain is metal. If that shows no results, try the same using some of the powdered shock, but let it sit for an hour (Trichlor pucks are also good for this) - this tests for organics. Finding out the type of stain is the first step in treating it.
While I'm at it, why do you keep the return 'eyeballs' so tight? They work just fine without being 'reefed in' and it's much easier to change the direction of them.

[DavidD]

Jake,

Waste assessment is pretty good in my opinion, the only thing you've changed is the method of delivery per se. I have seen the plastic on eyeballs, skimmers and steps turn a yellowish color before. I believe there are few things that can cause this besides metal stains and scaling. Not to say that these apply to you but they are extremely low PH, UV and copper. The pool that I'm referring is an above ground and they used Pristine Blue for a few seasons. My friend told me that they noticed the change in color after a few months of use and when I tested their water, sure enough the PH was less than 6.8! I also tested for copper and it was above 1ppm so we drained and refilled.

Now, for the ascorbic acid, have you tested a spot yet? If not, that is the first thing to do. You can test using a Vitamin C tablet, cheaper the brand the better. If it does work, dose your pool with polyquat (a.k.a. Algaecide 60%) to help ward of the green and go for it. You can bring the chlorine back up slowly in a few days. Be sure to follow the recommendations in the Stain section, paying close attention to all post by mbar. Marie helped me out tremendously with my in ground fiberglass pools a few years back. I generally treat my pool a couple of times a season with the ascorbic acid and by the way, the pool store tells me I have no metals as well. For some reason though, I get these grey stains and the ascorbic does the trick.:)

Dave

[Jakebear]

Waste and Dave --- and others.

Again, thanks for your help. Here’s where things stand.

There is no gritty feel to the stain, and TA and CH are 80 and 240 respectively, pH is 7.5.

Last week I ordered a Taylor Iron Test Kit (K-1716) and I already had the Taylor Low Range Copper Kit (K-1730). Got it the next day (really fast service from Taylor).

This morning I finally got around to running both tests ---- Iron came up 0 in the pool and 0 in my well water. Copper also tested 0 in both environments.

I tried the Ascorbic Acid test on the Eye Ball escutcheon (it is quite yellow). The stain disappeared IMMEDIATELY!!!!


So ---- now I know what to do ----- but being who I am and the way I am:D , ----- I still want to know why the switch to Ultra Bleach caused the problem. And since I have no Copper or Iron ----- What the heck is it?

BTW the reason I keep the eyeballs tight is because the Robot takes them off and eats them !!!! (Hungry little bugger):eek:

Here are the numbers for today:

Water Temp 83
pH 7.5 by titration
FC 5.8 ppm (FAS-DPD)
TC 5.8 ppm (FAS-DPD)
CC 0 ppm (FAS-DPD)
TA 80 ppm (by titration)
CH 240 ppm (by titration)
Phosphates 200 ppm
CYA = 50 ?? (turbidimetric) depending on who looks at it --- I HATE THIS TEST!!!!

[chem geek]

So ---- now I know what to do ----- but being who I am and the way I am:D , ----- I still want to know why the switch to Ultra Bleach caused the problem. And since I have no Copper or Iron ----- What the heck is it?

Marie (mbar) is an expert in stains so could probably help explain this with more real-world experience than I (so perhaps you should re-post your question in the Stains and Metal Matters (http://www.poolforum.com/pf2/forumdisplay.php?f=139) forum), but it is known chemically that higher pH precipitates metals out of water and can therefore cause staining. Bleach is somewhat high in pH at 11 and Ultra Bleach may be slightly higher due to somewhat higher chlorine content (6-7.35% for Ultra vs. 6.15% for Regular Clorox bleach). Chlorinating liquid at 12.5% sodium hypochlorite concentration is even higher in pH at around 13.

When you add the chlorine to your pool, this higher pH may precipitate the metals in the region where the chlorine is "spreading out" from where you pour it. Eventually, though, the dilution of the chlorine in the total pool water volume will lower its pH below the level where precipitation will occur. If this is what was happening to you, then I would expect most of the staining to occur wherever it is you poured your chlorine. Is that the case? As for why no iron or copper is measured in the water, perhaps you precipitated it all out from the use of the chlorine -- either that or the stain is something other than copper or iron (a true mystery!).

Richard

[Jakebear]

Hi Richard,
Yep --- a mystery.:confused: The stain was noticed on the steps and skimmer boxes when we lowered the water level about 3' (1500 gallons) working on getting the CYA down. (it's working slowly but-----). Like I've mentioned the liquid bleach was the only (apparent) change.

I pour the bleach in at the return stream about a foot from the edge at the three jets. Then stand on the diving board and spray (pitch) the remainder out across the surface of the deep end of the pool.

The stain is not localized so I doubt it is a result of direct contact.

I'm making preparations to do the stain removal (L-Ascorbic Acid) and metal chelating removal process (Versine Acid EDTA [from the MSDS]) . I just can't figure what chemicals are part of the reaction that caused the stain(which is why I posted here).

[mbar]

I was just reading this post, and I am as surprised as all of you as to why switching to bleach would cause this problem. I have found the complete opposite - cal hypo usually brings the stains out in my fiberglass pool. This is the way stains form in my experience. When there are any metals in the water - and metals come from dust, fertilizer, and who knows what else, even calcium is a metal, so even though the water doesn't test that metals are present in the water idoes not mean that aren't any. I never have metals show up in my tests, yet I get stains on my fiberglass pool if there isn't enough sequestering agent in the water no matter what I do. The fact that it is only on your return jets and skimmer is not a surprise to me, as these are made out of fiberglass (steps) and plastic. I read on a fiberglass website that fiberglass is magnetic, and it can draw out any metal that is in the water (I don't know if this is really true, but it may be why fiberglass stains and plates more than other pools). So if this is the case , then maybe it is why you only got stains on these parts of your pool. I know that the stain forms when the high chlorine reacts with high ph, and any metal that comes in contact with this solution will fall out. I can't answer why the calhypo never did this in your pool and bleach does, but it may have to do with the ph of the bleach. I have found that everyones water in the pool is different, and can react differently with different chemicals. There is just something a little different that is reacting with something else - So I understand why you want to know what it is. Sorry I can't help with that:confused:. Let us know if you do figure it out, so we can learn and help others.

You may just want to lower your ph to 7.2, and add a sequestering agent and see if the stains come off. If you do decide to do the ascorbic acid, you shouldn't need a lot, and you can start to bring up your chlorine right away. Just keep your ph low while raising the chlorine.

If you don't like the bleach, you can always swith back to what you were using before - if it ain't broke don't fix it:)

[Jakebear]

Hi Marie, (If you want to move this to the stain side --- go ahead)

Like I said to Richard --- It's a mystery!! I was just getting ready to post on the stain forum --- when I came to clip the thread URL --- Here you are!!

I keep trying to think what the cause is but obviously I'm not getting any where. Over the last 4 years we have tried all the JUNK (before we found this site) including Nature 2, Pool Genie, various sundry of cleaners and chlorine mixes etc. etc. so who knows what's left hanging around from the past. That said --- none of the "junk" has been present this season (except for residual).

As mentioned I'm dropping the Cl etc. to get ready for the Ascorbic acid which will get followed up with the Chelating agent --- Hopefully all without going to green, pink, yellow or black. I'll keep you posted.