Chemicals Slipping Out of Control....

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Got my kit today and the results are in...

FC 2.5
CC .5
TC 3.0
pH - 6.8
CH 600ppm (on 1st test) 545ppm on second test
TA 120
CYA 100

If I understand this right, it looks like my ph is low, my chlorine is ok, my calcium is really high, my Alkalinity is on the high side of normal, and my CYA is (not surprisingly) very high.

My pool still looks crystal clear and I have not added any chlorine since yesterday morning. So what now?

Thanks so much in advance!
Kristina

P.S. Is it ok for kids to swim in as is? Niece is coming over and kiddos want to get in the pool that just hit 79 degrees!
 
that low of ph might cause eye irritation...the FC level is way too low if CYA is 100 but likely much higher.

I would raise the FC to at least 12 for now if you have swimming going on. That would make the FC effective/sanitizing
if the CYA is truly 100.

CYA test only goes to 100, you need to do a dilluted test to get a more accurate reading.

take 1/2 tap water and half pool water in your cya test, then multiply your test result x2 to
get a more accurate reading.

also make sure you do the cya test properly with your back to full sun, holding the tube
at waist level, shaded by you.

CH is a bit high, but deal with that later.
 
borjis said:
CYA test only goes to 100, you need to do a dilluted test to get a more accurate reading.
Click to expand...
100 is the limit of the CYA test, so at this level we are unsure if it is 100 or some number above 100. Don't equate “just a little over 100” to a number, the tube is not marked for such extrapolation. At this point I would recommend at least a 33% water exchange to get the CYA down. I just want to caution you that in areas with a high water table lowering the water too much can “float” the pool out of the ground.


Now, if you want to try a diluted test mix 50% pool water with 50% tap water. Use this mixed sample as your test water. Multiply the result by 2 for your CYA level.

In the past we may have recommended further dilutions but history has shown that even a 1:1 dilution introduces error into the computation so your final number is not precise.. Further dilutions introduces errors that are just too high to make the test results usable.
 
I know, thats why I said dilluted test.

It worked well enough for me when my first pool was 300+ and got it down with partial drains/refills.

I guess I should have said "more general reading" cuz your right more accurate it is not :)
 
kikiganz said:
How do i know if I have a high water table?

Also, is it necessary to do the test with half tap water to find out the exact amount or just a "if you want to know"?
Click to expand...
Generally folks in the construction industry around you will know if there is a high water table. You say you are "Atlanta", but is that downtown, Buckhead or generally something like Cobb County or Dekalb? If you were next to the Kennesaw Mountain Battlefield Park I would say you are probably not in a high water table area, but in some low lying areas you might be. The local building department may be able to help you in this area.

As a point of reference, my current house is the low lot in the development. When it rains everyone's water comes to me. The day after a heavy rain I can actually watch water pushing up through the expansion cracks in my driveway. Last year while cleaning a grout line I accidentally punched through the grout with a screwdriver. Water pressure turned this little hole into a fountain, squirting water into my pool for a couple of hours. So in my case I know I have a high water table.

Now, to the diluted test. Every time you make a dilution you expand the normal error factor in the test, but it can give you an idea of the area you are in. If you did a 50/50 dilution test like I used as an example and ended up with 60, then you would know that you were "in the area" of 120 for your CYA. This would yield about an 80 CYA if you did the 33% drain/refill. But, if on a diluted test you came up with 100 again (I did my first time) you would know that to get the CYA to a manageable level you will be replacing most of your water.
 
To do the CYA test diluted... measuring carefully, get 2 cups of pool water and pour it in a clean jug. Add 2 cups of tap water to the jug and stir it up. Then take your little sample from that water. Whatever the reading is, double it to get a rough CYA level.
(edited to remove "reasonably correct CYA level")

If it's still 100 - Get 2 cups of pool water and pour it in a clean jug. Add 4 cups of tap water to the jug and stir it up. Then take your little sample from that water. Whatever the reading is, triple it to get a rough CYA level.

If you're struggling with the visual aspect of the test, with the tube at waist height and sun behind you, try just glancing (look away then look back at the dot) and if you still see the dot, add a little more sample.

To gain confidence in your result, you can do the CYA test multiple times without adding more reagent. It's OK to pour from the tube with the black dot back into the little mixing bottle, give it a shake, and then test again. This helps you have confidence in the reading without using more reagent.
 
Last edited:
needsajet said:
To do the CYA test diluted... measuring carefully, get 2 cups of pool water and pour it in a clean jug. Add 2 cups of tap water to the jug and stir it up. Then take your little sample from that water. Whatever the reading is, double it to get reasonably correct CYA level.

If it's still 100 - Get 2 cups of pool water and pour it in a clean jug. Add 4 cups of tap water to the jug and stir it up. Then take your little sample from that water. Whatever the reading is, triple it to get reasonably correct CYA level.

If you're struggling with the visual aspect of the test, with the tube at waist height and sun behind you, try just glancing (look away then look back at the dot) and if you still see the dot, add a little more sample.

To gain confidence in your result, you can do the CYA test multiple times without adding more reagent. It's OK to pour from the tube with the black dot back into the little mixing bottle, give it a shake, and then test again. This helps you have confidence in the reading without using more reagent.
Click to expand...
The only thing I can quibble with is the "reasonably correct CYA level" comment. As I said above, history has shown that even a 1:1 dilution introduces error into the computation so your final number is not precise.. Further dilutions introduces errors that are just too high to make the test results usable.
 
So here is my husband's question. Does the CYA issue HAVE to be fixed? Is it necessary to swim? What are the pros and cons of doing so and not doing so.

tim5055...so you are familiar with the area :). We are in East Cobb. We have a Roswell address but are still inside Cobb County. I am going to try to figure out who I can ask this.

Again...thanks for the info all!
 

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kikiganz said:
So here is my husband's question. Does the CYA issue HAVE to be fixed? Is it necessary to swim? What are the pros and cons of doing so and not doing so.

tim5055...so you are familiar with the area :). We are in East Cobb. We have a Roswell address but are still inside Cobb County. I am going to try to figure out who I can ask this.

Again...thanks for the info all!
Click to expand...
yea, I lived next to the Battelfield Park for five years. A call to the building department might help or just pay attention to nearby construction. If someone is running a backhoe, does the pit fill with water quickly?

As to your husbands question, no you can let the CYA be and just work it down over time. What I did -

* I was aggressive on when and how long I back washed my sand filter

* If I didn't think I used much water in a month I might pump out four or five inches of water and replace it.

* I rigged up a device on one of my gutter downspouts to harvest rainwater and put it in the pool

It took me close to 18 months, but just this morning I had to add CYA.....

The downside -

You have to be diligent on never letting your FC drop below what is recommended on the [FC/CYA][/FC/CYA]. If you let it slip and algae gets a foot hold it is near impossible to eradicate at high CYA levels due to the amount of chlorine necessary. You also have an issue I didn't, metals. I will defer to one of our experts in that area, but staining and the possibility of the metals coming out of solution due to a rapid chlorine increase is possible.
 
We are going to drain the pool 1/3 but we have a really dumb question. Do we need to rent a pump to do this or can we backwash 1/3 out? Our concern is does it pull from the bottom or from the skimmer. If the skimmer then we would get air in right? Thanks!
 
There might be a valve to shut off the water from the skimmer. That'll tell you if you can pull off the drain.

If you have a vacuum hose and a slope you can siphon off that way.
 
Ok...I think it is going to finish filling just about the time the sun goes down. I know we cannot do the CYA test without sunlight. Do I need to worry about getting chemicals into it tonight or is it ok to sit over night and handle in morning?
 
kikiganz said:
Ok...I think it is going to finish filling just about the time the sun goes down. I know we cannot do the CYA test without sunlight. Do I need to worry about getting chemicals into it tonight or is it ok to sit over night and handle in morning?
Click to expand...
the only thing I would worry about is pH & chlorine. Test and adjust them with the old CYA. That will make the FC a little high, but high is better than low.
 

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