Question about shock and chlorine

[donovan.lambright]

I've got a 15' x 48" Intex Easy Set pool. I don't know the exact capacity but, based on googling the pool and looking at various listings, I believe it's in the neighborhood of 4,000 gallons. This is only my second summer with the pool. When I set it up a week ago, I added a whole pound of shock along with 5 or 6 one inch chlorine tablets in the floater. This was about 3 times as much shock as needed, of course, as I found out later when I referred to my notes from last year (that's what I get trying to work from memory). The chlorine levels weren't rising as fast as I had expected and I started to worry about algae. Therefore, I added 6 more chlorine tablets a couple of days later.

Now, my chlorine levels are too high. I took the chlorine floater out of the pool about 2 days ago and have been testing twice a day. I assumed the levels would have started dropping by now but there's been no change. The weather has been on the cool and cloudy side and I wonder if that is a factor (I seem to recall reading that heat and sunlight speed up chlorine dissipation). I'm testing with the AquaChem kit that uses 5 drops of two chemicals, one for chlorine and one for pH. I'm sure you know the one I mean. pH looks pretty good, although I did have to lower it a few days ago after a big rainstorm.

I'm wondering if I'm on the right track here or whether I should be doing something else. Sorry if I haven't posted all the relevant information. Or a bunch of irrelevant information. :-) Thanks for any information you can provide.

Donovan

[aylad]

Hi Donovan, and welcome to the forum!!

When you say your levels are too high, what exactly do you mean? Can you post results for your chlorine and pH, taken with your kit? If your chlorine is higher than what the yellow scale will register, you can always dilute the pool water 1:1 with distilled water, mix, and test from that--and multiply your test result x 2. It's a ballpark, but it gives us more information than "too high".

What was the ingredient in the shock? How does your water look?

Sunlight will bring the chlorine down (as will a large bather load ), but you may still be okay to swim...

[donovan.lambright]

Thanks for the welcome!

I am at work right now and can't give you the exact numbers but will post tonight after I test again. I can tell you right now, though, that the chlorine is off the yellow scale. pH is in the normal zone.

The water is very clear, except when I run the pump which makes it cloudy. There's some fine dirt in the pool which is getting stirred up so I think that's a red herring. I vacuumed a lot out yesterday but there was still some settled on the bottom this morning.

You mentioned it maybe being OK to swim. That leads me to the other question I was going to post today. I was going to make it a separate thread but since we're already here... We did go ahead and swim on Saturday (a couple of days ago) even though the chlorine was high. Two of us (me and a four-year old) are fine. The third (six-year old) woke up the next morning with tiny red bumps all over. Very itchy. I remember her being more sensitive last year, too, so I can't say I'm that surprised. We're treating her with various lotions and baking soda in the bathtub but swimming is out of the question for awhile. Which leaves me with a question. Is this the "pool rash" I hear so much about? And, if so, what causes it? I've read online about high chlorine and bacteria being known causes. Is there any way to know which is which?

The fact that only one of us got it PLUS the high chlorine levels in the water (which I'd think would kill bacteria) make me pretty sure it was the chlorine that did it. Still, I've yet to see anything online that really explains the difference between the two causes.

Thanks again and let me know if I need to move that second issue to a new thread.

Donovan

[donovan.lambright]

OK, got some numbers. The chlorine level has finally come down and is around 1.5 to 3.0. I'm having a hard time pinpointing it further because I'm having a hard time seeing the color difference between the two levels. I think I need to get a more precise testing kit. pH is 7.6. The active ingredient in the shock is Sodium dichloro-s-triazinetrione. As I said above, the water is crystal clear. I mentioned it getting cloudy when I ran the filtering pump; I ran it all last night and the water stayed clear this time.

[Watermom]

You are right that you need a good test kit. The only one we truly recommend is the Taylor K-2006 or 2006C. You can get it through the test kit page in my signature below. It is only available online however, so you'll need something to use while you wait on your good kit. Get a cheap OTO (yellow drops) / phenol test kit, or if available at YOUR Walmart (check availability), get the HTH 6-way DROPS test kit, which is compatible with the Taylor K2006. Test the pool as soon and you can, and post the results. If you get the 6-way kit, ALSO test the water you FILL the pool with, especially if it's a well, and post THOSE results as well. (The HTH is the best available kit you're likely to find locally, but it's not the K-2006. It can only provide rough measurements chlorine levels above 5 ppm, and it measures "TOTAL" hardness, rather than "CALCIUM" hardness, which is not ideal.)

It's much easier to answer your questions, when we know something about your pool. We often 'waste' the first few posts back and forth collecting information. So, please complete our new Pool Chart form -- it takes about 30 seconds, but will save much more than that.

Pool Chart Entry Form
Pool Chart Results

Can you look on the label of the dichlor package and see what other ingredients are listed? Some pool chemical companies are starting to add a bunch of unwanted stuff.

One very important reading that we need is your CYA level. If you don't find the HTH 6-Way kit, see if you can find a reputable pool store who can test your CYA level for you. (By the way, that is one of the tests that comes in the K-2006 kit.) You only want them to do the test for you if they do the "disappearing black dot" test. Don't let them talk you into buying a bunch of stuff while you are there. And, they will try!

Hope this helps some.

[donovan.lambright]

Just to be clear, I've been checking the chlorine with the OTO kit. It looks like the local WalMart has the HTH kit and I'll pick one up this afternoon after work. The Taylor kit looks nice and I'll see about getting one ordered. I'll check the CYA level and post results tonight.

I tried to fill out the Pool Chart Entry Form but got hung up on my PF User ID. It's required and I can't seem to find it. I don't have access to My Profile yet, presumably because I'm still a Trial Member.

About the shock. The package doesn't list any other ingredients other than the dichlor. It just says 58.2% dichlor and 41.8% Other Ingredients. :-)

[aylad]

Your PF user ID is your screen name...

[donovan.lambright]

Your PF user ID is your screen name...

Well, so it is. Somehow, I got it into my head that it was asking for a number. I have now filled the form out.

I also picked up the hth 6-way test kit and have run all the tests:
Chlorine 2
Bromine 4
pH 7.8
Alkalinity 260 ppm
Hardness 310 ppm
CYA 30+ ppm (I have to add the plus because the black dot in the test vial had not disappeared yet when I reached 30 and couldn't add any more liquid)

[aylad]

Your numbers don't look too bad...you don't have a bromine pool, so you can ignore that one. And your CYA is less than 30, if you ran out of room in the tube before the dot disappeared, so you're ok with chlorine at 1-3 ppm. Your hardness is a bit high but shouldn't cause you any problems unless you chlorinate with cal-hypo, and then you're asking for milky water problems, so I would avoid using that form of chlorine. Your alk is high too, but if that's the same as your fill water, then there's not much to be gained from trying to lower it.

It would be interesting for you to test the water at night for chlorine, and then test it again in the morning before the sun hits the pool, to see if you're losing chlorine overnight. If so, then it's possible that the CC resulting from the chlorine fight going on in the pool might have caused the rash that you saw.

Janet

[Watermom]

First of all, you don't have a bromine pool so just ignore that side of the tester. Also, if the black dot was still visible, then you have less than 30ppm of CYA, not more.

Your alk, pH and calcium hardness are all high. Run the calcium and alk test on your fill water and post the results.

Read the using muriatic acid safely page linked in my signature below and also the following about lowering alk. Lowering Alkalinity Step-by-Step

Then, work on lowering your pH to 7.2ish and the alk to 80-100 or so.