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I would think that it would work since the net effect of adding sodium percarbonate is adding hydrogen peroxide and sodium carbonate.Quote:
Originally Posted by PoolDoc
The only thing is that the baqua shock is a 'stabilized' peroxide (most likely stabilized with citric acid) but I would think the sodium carbonate would raise the ph enough to destabilize it.
I will do whatever you guys think is best.
We have let the chlorine levels drop in the pool for the last week and we have been swimming. We haven't had any ill effects. The combined chlorine has been lower lately. The funny thing is since several days before we started swimming, we have not smelled any chlorine smell outside, not even at the pool. When I tested the pool 2 days ago, the combined chlorine was 2 and the fcl was 5.
Today the fcl was 3 and the ccl was 0. Several days ago, my cya was low so I broke up a 3 inch tab and put it in and put another tab in the floater since I didn't have any stabilizer except in the tabs. I thought my combined chlorine would go through the roof when I put the tabs in but so far so good.
If I need to get the sodium percarbonate and dry acid, where would I get dry acid?
Follow the procedure and then clean the filter, replace the sand and hopefully, we're good to go!
Yes, Arm & Hammer Super Washing Soda (careful: NOT the laundry detergent) can be used for the "pH Up" sodium carbonate and "BaquaShock" can be used for the hydrogen peroxide. However, to dose this properly, we need to know the concentration of hydrogen peroxide in the product. From this link, it says it is 27% hydrogen peroxide. So remember what I wrote earlier that by weight, 1 pound of sodium percarbonate is 0.675 pounds sodium carbonate and 0.325 pounds hydrogen peroxide. So 0.325 pounds hydrogen peroxide is 1.2 pounds of BaquaShock. If I assume a density of around 1.1 g/ml, then 1.2 pounds of BaquaShock is around 17-1/2 fluid ounces or a little over 2 cups.Quote:
Originally Posted by PoolDoc
So let's use the 1 pound sodium percarbonate per 2000 gallons amount so for 15,000 gallons this would be 5 pounds of washing soda (sodium carbonate) and about 4 quarts of BaquaShock. The washing soda will raise the TA by 38 ppm and could raise the pH to 8.8 but the BaquaShock will lower the pH as it oxidizes whatever is left in the pool. Hopefully you don't have a lot of metal in your water since the higher pH could stain. So add this recommended amount of washing soda and BaquaShock and wait 24 hours with the pump running the entire time, though technically you saw results in your bucket test after 8 hours. You should then measure zero CC. You'll then need to start adding bleach until you get an FC reading.
Hey Chem_Geek, Waterbear;
If you can work this out as a recipe - so many boxes of A&G washing soda and so many jugs of BaquaShok per 10,000, it could potentially help a bunch of people.
Just sayin'
We don't really know if the 1 pound per 2000 gallons (5 pounds per 10,000 gallons) is the proper dosage. While it looks like it might work for reesie's situation, it looks like aciam's situation is more severe. At any rate, for this dosage rate this translates to 3.4 pounds (1 55-ounce box) of Arm & Hammer Super Washing Soda and 11 cups (about 3 quarts; 3/4 of one gallon) of BaquaShock per 10,000 gallons.
I suppose one could start with this sort of dosing and then measure the pool water after 24 hours to see if there is still CC in which case one can add more.
My husband and child wanted to swim over the weekend so we waited until 4:00 pm today to add the washing soda and BaquaShock. I tested before we added them.
fcl 3
tcl 5
ccl 2
alk 170
cya 30
ph 7.5
I tested again at 9:00 pm
fcl 1
tcl 1
ccl 0
alk 200
ph off the scale
Chem_geek and Waterbear said wait 24 hours and start adding chlorine, if it's 0 ccl, until it holds a fcl reading. Lower ph before adding chlorine or after? How much chlorine should I add at a time and how often? I have cal hypo and 3 inch tablets and bleach ( if the store doesn't run out again!).
Then clean filter thoroughly and change sand.
Again, thanks for the help! All of you guys are the best!
I tested 0 fcl and 0 tcl and 0 combined chlorine so now I'm going to start adding chlorine. Any advice as to how much to add at a time and how often?
You'll want to add Cyanuric Acid to the water as well as chlorine or else sunlight will break down your chlorine too quickly. Your 3" tablets will add both chlorine and CYA, but will take too long to add either. The Cal-Hypo is fine if your Calcium Hardness (CH) isn't high and the bleach is also fine. So you'll need to get some pure CYA or perhaps could get some Dichlor which dissolves quickly and can be added to give you both chlorine and CYA (at least some) initially. Up to you -- whatever is easiest for you to get. Most people get pure CYA and put it in a sock or panty hose to hang over a return or in the skimmer for faster dissolving (some add it slowly to the skimmer to get caught in the filter, but that usually takes longer to dissolve).
If you have some CYA in the water, you can get your FC up to around 3 ppm to start with, not more than 5 ppm, but just note that it may drop quickly initially until you get more CYA in the water so you'll probably be adding chlorine multiple times per day the first day or two.
I have good news and bad news...I think. I don't have any combined chlorine so far. But I also don't seem to be having any luck at getting my free chlorine or total chlorine levels up.
My cya is 60
ph 7.6
alk 150
the most I've gotten the fcl to is 1, tcl was the same
I've added 16 ozs. cal hypo (65%) at a time
Tonight we added 24 ozs.
Should I go ahead and change the sand now or wait until I can get it to hold a fcl reading?
Change the sand! There is probably a lot of gunk in their creating the chlorine demand.
Normally we NEVER recommend changing sand, but after a bacquajunk usage or conversion you must.
After this stick with chlorine and you'll never have to change your sand again. I'm 9 years on the same sand. Watermom is 14 or 15 years on the same sand.
Carl
Nah, I'm "only" on my 11th season with the same sand. It is Al who is on year 14 or 15.
It's been so long my memory's starting to go! :)
We changed the sand 7/1/2011. No combined chlorine most of the time, but I still can't get a good free chlorine reading. I did have a combined chlorine once of .5 I'm averaging putting 12 - 24 ozs of 65% cal-hypo every night.
My readings tonight were
fcl 1.5
tcl 1.5
ccl 0
ph 8.0
alk 140
cya 60
I put 12 ozs. cal hypo and 20 ozs. dry acid to lower ph
Should I be using so much every day?
The water is great! No smell, beautifully clear!
12 ounces of 65% Cal-Hypo in 15,000 gallons is 3.9 ppm FC so yes that is much higher than normal, especially since it's 12-24 so 4-8 ppm FC every day. See this thread where the most typical daily chlorine usage is around 2 ppm FC and usually ranges from 1.5 to 3 ppm for most residential pools.
As for the acid and high pH, that is because of your high TA level. The TA will drop over time and the pH will become more stable. You can add more acid to lower the pH to speed up this process, but right now I think we've got to figure out the high chlorine usage. Perhaps its persistent remnants from the Baquacil conversion. I'd track your usage over the next week or so to see if it slows down. Quite frankly, if we knew in advance how bad this conversion was going to be for you, then I would have suggested changing the water instead, as painful as that might have been.
Note that your Calcium Hardness (CH) level will increase over time since for every 10 ppm FC added by Cal-Hypo it also increases CH by at least 7 ppm.
The readings have been good.
7/10/2011
fcl 2
tcl 2
ccl 0
ph 7.6
alk 140
ch 130
cya 60
I put 48 ozs. dry acid in and 9 ozs. cal hypo.
We now believe we have a leak but we're holding the chlorine and we don't have combined chlorine!!! We're losing more water than we should be losing to evaporation. We've spent the last week going over every inch of the liner trying to find a leak. We haven't been able to find it, but have found an area that the sand underneath has shifted, so we have an area to look at harder.
I haven't put anything else in until tonight because we are letting the water level drop to see how low it will go to see if the hole is in the bottom or on the walls. We had to cut the pump off when it dropped below the skimmer. I checked the water tonight.
fcl 1.0
tcl 1.0
ph 7.4
alk 125
cya 60
ch 130
Reesie,
I moved your question to the Construction and Repair section of the forum since this issue has nothing to do with the Baquacil forum. You can find your new thread here:
http://www.poolforum.com/pf2/showthr...-a-vinyl-liner
I no longer have combined chlorine. The chlorine demand has settled down. I've only been using 1.5-2 ppm a day for the last 10 days. I'm still battling high ph, though.
fcl 4
tcl 4
ccl 0
alk 125
ch 140
ph 7.4
cya 50
I just had to put 42 ozs. dry acid in to bring the ph down to 7.4
I'm having to put around 40 ozs. dry acid in every week to lower ph. Is this normal? I don't remember ever having to adjust the ph so often.
Drop your TA down to about 80 ppm and your pH will not be rising as fast. Also, muriatic acid is cheaper and more effectie than dry acid.
Okay, thanks, we'll try that.