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!!

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.

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