Starting Conversion Using Sodium Percarbonate

mickey4paws

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Apr 10, 2009
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S.E. MI
Yesterday we opened the pool for the season, and drained out all but about a foot of water (in the shallow end), and we are now in the process of refilling. We still have about a foot of water to go yet. We decided to take a test to the pool store (mostly because I was dying of curiosity as to Baquacil levels). Anyway, this is the results of the test:

Sanitizer: 32 - which is in the ideal level range :(
Shock/Oxidizer: 1
TA: 87
PH 7.5
Calcium: 195

My question is are we supposed to be looking at the sanitizer reading or the oxidizer reading, or both?

Tomorrow morning we're putting in the sodium percarbonate. They say to filter it for 24 hours, then recheck levels. If not at zero Baquacil, then filter another 24 hours. We are supposed to be backwashing during this, correct? If so, how often, just as needed?

Once we have zero Baquacil, we will start adding chlorine (I bought 4 gallons of liquid chlorine - it seemed more cost effective than buying bleach). Since the chlorine is still on sale for a couple days, I want to buy some more, but don't know how much more I might need to use once we're at zero Baquacil.

Lastly, regarding changing the sand: Do we change it before we add any chlorine? My PB says he probably can't get back out until the weekend to do the sand change. I'm just trying to figure out how important the timing of that sand change is.

Lastly, lastly :) I bought the TF100 test kit. Is there a tutorial for dummies? I know the test kit doesn't test for baquacil, but while doing the conversion, I can still test for other things, correct?

Any help is greatly appreciated. I'm feeling kinda lost.
 
Re: Starting Conversion - Finally! and have some questions

Backwash as needed through the entire process.

Do not change the sand until the very end of the conversion, after the FC level holds at 15 overnight.

It is the "Sanitizer" level that you want to go to zero.

Using the TF100 is really quite easy. There are more complex directions available, but not simpler directions. The directions that come with the kit are quite simple.

Guessing quantities is difficult. I suspect you will need much more chlorine than that, but there is no telling.

Good Luck!
 
Re: Starting Conversion - Finally! and have some questions

Thanks so much for the replies :) This morning we put the sodium percarbonate in and will now filter for 24 hours and retest the Baq level. I'm really disappointed it was so high after draining almost all the water out of the pool. I guess it must stick inside the pipes and equipment pretty well. The sodium percarbonate was kinda bubbling at the top, making the worms that were on the bottom come to the surface. There were a million of them in the leaf skimmer :shock:

I wonder if with using the sodium percarbonate, the pool turns green like it does with bleach. So far no color change. I took some pics this morning but haven't uploaded them yet.

We put in the automatic cleaner this morning (it is self-powered & doesn't run off the pump). I don't think that should disturb the conversion process with the sodium percarbonate, right? The sodium percarbonate is all dissolved now.
 
Re: Starting Conversion - Finally! and have some questions

Great! We would love to see a picture :)

The cleaner will actually help the conversion by improving water circulation and getting any debris out of the pool. However, it isn't generally a great idea to run a cleaner during a baquacil conversion. First, the oxidizer levels are very high, which could affect metal parts in the cleaner, and second because if you do get goo (which is less common with sodium percarbonate) in the cleaner it can get clogged up and be very difficult to clean.
 
Re: Starting Conversion - Finally! and have some questions

Uh oh. Maybe I shouldn't have put the cleaner in then. I just called home and asked my husband to take it out of the pool. He said there is plastic type goo floating all over the pool. I hope this is a good sign that the sodium percarbonate is working.
 
Re: Starting Conversion - Finally! and have some questions

Ok, picture time :) Seems the sodium percarbonate doesn't change the water color but we have some gunk in there.
 

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Re: Starting Conversion - Finally! and have some questions

The water color will probably turn green and get worse. Buy more bleach!!! I changed my pool from baqua to BBB in the middle of the summer and uses about 95-174oz bottles. You will probably not need near that many but it will take a lot of bleach (a lot more than 4). I also had an algae problem all but 1 and 1/2 weeks last summer before I switched.

Good luck with your conversion and please be patient. This is not an over night project. Just make sure you keep your chlorine levels up to shock level until it is not loosing more than 1ppm.

Susan
 
Re: Starting Conversion - Finally! and have some questions

Thanks, Susan! :) Wow, that's a lot of bleach you used. At this point we haven't used bleach yet because we used sodium percarbonate. Tonight we will test for Baquacil level and see what to do next. From the instructions for a sodium percarbonate conversion, first you add it, then filter 24 hours, check Baquacil levels, and if not at zero yet, filter another 24 hours, and then recheck again. I guess if it's still not at zero, we will start adding bleach because we're all out of sodium percarbonate and it would take to long to get more.

This morning I filled up a glass with pool water and added bleach. It turned a very light green. Also, the pool doesn't have all that plastic type goo floating on the top like it did yesterday (it's probably all in my filter and pipes now :(
 

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Update: Just got back from having the water tested. Here are my results:

Baquacil sanitizer: 0 (yay!!!!!)
PH: 8.0
CH: 134
TA: 60
Baquacil shock/oxidizer: 4

Any suggestions would be greatly appreciated!
 
Shock your pool to the recommended level for your water volume using the pool calculator for the shock level as target.
Check chlorine level after about 1 to 2 hours and bring back up to shock level. You need to know your FC and CC level.
Just keep adding the chlorine and have lots of patience.

Good luck,

Susan
 
Re: Starting Conversion - Finally! and have some questions

JasonLion said:
Do not change the sand until the very end of the conversion, after the FC level holds at 15 overnight.

Hi Jason,
Here is where I'm very confused. According to the conversion with sodium percarbonate instructions, when you get to zero Baquacil sanitizer, then it says add chlorine to establish a 2.0 ppm FC. So using the pool calculator, I just added only 65 oz of 9% chlorine which would net 2.5 ppm FC. Does that sound right?
Or, should I be raising FC higher?

Also, at what point do I add CYA?

I am so confused :(
 
You want your shock level to be 15ppm.

Do NOT change your sand until you are done as the baq in the pool will infect the new sand and you'll have to change it again.

Be prepared for some pretty ugly water!

You will get no where fast by keeping the chlorine at 2ppm. :shock: Also, don't add CYA until the very end. It will make a conversion longer than it has to be. It would be a good idea to add bleach 3-4 times a day for the first couple days as the bleach eats up the baq. The chlorine will disapate fairly quickly.
 
I have seen a couple of cases where sodium percarbonate didn't quite finish the conversion, and none where it did fully finish the conversion. Because of that, the sequence I am explaining is a hybrid, start with sodium percarbonate, and finish with chlorine. If the sodium percarbonate finished the conversion you will only waste 10-15 ppm of chlorine using my directions.

1) Do a sodium percarbonate conversion till sanitizer reads 0
2) In the evening, raise FC to 15
3) wait one hour and then test the FC level (if below 10 do chlorine conversion)
4) the next morning, measure the FC level again

If the first FC measurement is below 10, or the two FC measurements differ by more than 1, you need to continue on with a chlorine conversion (raise FC to 15 frequently till it holds overnight). If the sodium percarbonate worked as advertised you will have the same FC level in the morning and you are nearly done with the conversion.

The final steps when FC holds overnight are to replace your filter media, and then add CYA. Maintain FC at 15 after that as long as CC is above 0.5.

If the sodium percarbonate does not work perfectly, and you go ahead and add replace the filter media and add CYA without the above procedure you will be stuck with days to weeks of shocking and possibly replacing the filter media again. If the sodium percarbonate does work perfectly, my sequence only adds 12 hours and 10 to 15 ppm of wasted chlorine.
 
Thank you so much for the replies. Regarding your instructions, Jason, we completed step one, and then last night added only 1/2 gallon chlorine. Maybe we should have been adding enough to shock levels? This morning I took a sample to the pool store and it shows 0 chlorine and PH at 9.0. Unfortunately I'm at work and can't leave, so when I get home around 5, I will add chlorine to raise to 15 ppm, and retest in an hour, and continue your instructions.

Here's the problem with the sand. The guy who is doing it for us has a tight schedule and we were hoping he'd do it on Saturday. But from the sound of it, maybe we should hold off a few more days. Would it be okay to not change the sand until Tuesday, even if our conversion is successful before that?

How hard is it to change the sand ourselves? I get nervous with the laterals, etc.

Thanks again, I really do appreciate the help!
 
Let us hope that the PH of 9 is a testing or transcription error. If the PH is really 9, you need to get it down to between 7.2 and 7.4 right away. Another possibility is that the FC level is actually very high and they are using a DPD chlorine test, which bleaches out and shows 0 at high FC levels. At high FC levels the PH test can read much higher than actual.

You really need your own FAS-DPD chlorine test to finish up a conversion, preferably an entire test kit. None of the other tests are reliable or precise enough to distinguish the finish condition, and you end up having to maintain a high FC level for several extra days just to be sure.

It is probably better to postpone changing the sand. If you change the sand too early the sand can get gunked up with baquacil residue and be ruined.
 
Thanks, Jason. I'm embarrassed to admit I just bought a TF100 kit and was doing the chlorine drop test this morning. I kept adding drop by drop and it was still pink. After 22 drops, I thought I must be doing something wrong, so that's when I took the sample to the pool store. The guy at the store did the test really fast (I guess it didn't help that the store was so crowded) so I wouldn't be surprised if the test isn't accurate.

Yesterday, when I went to the Baquacil store for testing, the sanitizer was at zero but the PH was at 8.0. We had some PH decreaser from last year that we added last night, so I'm really surprised that the PH would then go up to 9.0.

Do you think it's possible that my problems are because I only added 1/2 gallon of 9% chlorine last night, instead of adding shock level to make it 15 ppm? One good thing I guess is that the water hasn't turned green. In fact, the pool looks pretty clear so far.
 
22 drops is only a FC level of 11, so next time you try it you should keep going to at least 40 drops, or more, if it doesn't turn clear.

This evening, add 15 ppm of chlorine, give it 30 minutes to mix in, then test the FC level.

If FC is less than 10, add more chlorine aiming for a level of 15, wait 30 minutes, and test again.

Then tomorrow, test first thing in the morning and tell us what results you got.
 

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