What not to do $$$ Conversion to SWG

May 22, 2010
21
Am I glad I found this forum ... I'm tired of having the pool store suck the money from my bank account!!!
Sorry for being long winded here as I will try to bring you up to speed on what has taken place over the last few weeks during this conversion.

I have an Inground Vynil pool at 22500 gal, Hayward sand filter and 1.5hp pump as well as an in line chlorinator for 3" tablets. I am adding/converting to a Hayward Swim Pure SWG.

While trying to save money, I have purchased and installed the system myself but the pool store is guiding (raping) me through the conversion. I had purchased (along with the SWG) Monopersulfate to get rid of the Baquacil (at a starting point of 40ppm) and it did a really good job according to the pool store. And have backwashed numerous times and chemically cleaned the sand. The colors where not that impressive ... mostly a brownish grey that dissapated.

Here's where it gets costly!
I started the conversion 2 1/2 weeks ago, and so far have spent over :? :oops: $800 in Bioguard (among others) chemicals. After the first week and a half they had me change my sand stating that the baquacil was still in the filter and needed removed. After the second week I have installed the cell in line and am just trying to get the levels correct before turning the SWG on.

Here are the stats to date:
5-04-10
Baquacil 44
PH 8.1
TA 106
CH 225

Shock, shock, shock, $$$, $$$!!!

5-18-10
CYA 53 (after adding on 5-17 with a level of 22)
Total Chlorine 1.7
FC 0
PH 7.2
TA 103
Total Hardness 267 (probably due to all the calcium based shock, was as high as 299)

5-19-10
CYA 20 (why?, didn't backwash)
TC 3.2
FC 0.6
TA 113
Hardness 285

On the 18th my pool was back to a greenish Marguarita hue and they don't know why. And have since added algecide at their suggestion. I might add that I have been adding 3" trichlor tabs to the chlorinator throughout the conversion.

I have now purchased a Leslies DPD test kit, chlorine bleach, soda ash, baking soda ... and am trying to do this myself (with some guidance of course). Now being the 22nd, I am getting quite different readings with my test kit ... maybe I am doing this wrong, but here goes.
Yesterday AM:
FC 1
TC 8-10 (above the highest reading on my test kit of 5, just guessing.)
PH 7.8
TA 180
Added 2 lbs dichlor, 5 lbs low & slow to lower ph to 7.2 and try to get TA to come down.
Have also added a fountain for aeration.

Last night after adding 2 gallons of bleach:
FC 1
TC 10-12
PH 7.2
TA 160

And lastly this morning:
FC 1
TC 10-12
PH 7.2
TA 160

I plan on taking a water sample to Leslies (not my regular pool store) to get more accurate readings tomorrow.

Please advise, and thanks in advance. :hammer:
 
Re: What not to do ... Conversion to SWG

Welcome to TFP :wave:

Sorry things have gone like they have but lets take that as water under the steps. I know it's not easy.

Now lets start fresh.

I know you've spent a lot of money but I'm about to ask you to spend a little more. You really need a good test kit. You need to be able to test higher FC & CC than you can now. You can buy individual tests but by the time you buy what you really need it may be easier to buy a full kit. I suggest the TF-100 XL because I don't think you ever finished the conversion. You'll also need to buy an enormous amount of bleach.

I wouldn't waste any more money trying to fix this until you can test what you have.

In order to finish the conversion you're going to need to be able to shock and test at least that high. You're also going to need to do an overnight drop test.

Taking a sample to Leslies might be better but I still wouldn't trust it. Most times they can't test any higher than 10ppm and even then it may not be accurate.
 
Somehow, I knew that response ... LOL
What is your opinion on using the remainder of the Dichlor shock and 3" trichlor tablets? Are they adding too much CYA that is in turn inhibiting the added chlorine, or am I confused?
 
I would stop using the trichlor with having so much of a variation on your CYA test. I have never had a pool store be able to give me the same result as what I get or even close. Plus at a lower CYA the amount of bleach you will have to use is less due to shock level. As advised I would order the kit so you can get more accurate results at home and only buy what you need.

Welcome.
 
You want to stop using dichlor and trichlor until the conversion is truly complete. The higher the CYA level, the slower the conversion will go. Since both dichlor and trichlor add CYA, they will just slow things down.

You really need a top quality test kit of your own to finish the conversion without wasting a lot of chlorine. The most crucial test for a baquacil conversion is the FAS-DPD chlorine test. The DPD chlorine test is simply not usable at the FC levels you will need to use to finish off the conversion.
 
There's no way of knowing just how close you are because we don't know how long it's going to take to oxidize whatever the PS had you put in there.

Depending on where you're located TFtestkits can have it to you in a couple of days. Alternately, some Leslies have a service test kit that's the equivilent of the Taylor K-2006. If you go to Leslies make sure they don't sell you the one with just the DPD test. They have been known to tell people they're the same but they're not. The problem with the K-2006 in your situation is that the amount of reagents are not goint to be enough to get you through the conversion so you'll be trying to find more reagents in the middle of the conversion. During the conversion, consistancy is the key to making it go as quickly as possible.
 
If your test results are correct, you have quite a ways to go. But, as I said, the DPD test is not reliable when the FC/TC level is 10 or higher, so your actual numbers might be different.

It is quite rare for pool stores to stock the FAS-DPD test, though every once in a while they do. I suggest you get it over the Internet. TFTestKits.Net has a great test kit, and they also sell the FAS-DPD test separately.

For right now, the most interesting number is your current CYA level. That will tell us how high you want FC to be. Then you can try using the DPD chlorine test with dilution to get an approximate idea of your FC level. You will need some chlorine free water to do the dilution, distilled water is good.

Hum, Bama Rambler already said most of this.
 
To use dilution, mix one part of pool water with three equal size parts of chlorine free water, do the test with that, and then multiply the result by four. Depending on what you expect the final level to be, you can modify the dilution ratio so you can get better results at specific levels. 1 to 1 - multiply by 2. 1 to 2 - multiply by 3. 1 to 4 - multiply by 5. The more dilution you use, the less precise the results. Above about 1 to 4 the results are so imprecise that they are essentially useless.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Ideally you want CYA to be zero during the conversion. Since lowering CYA requires replacing water, that isn't practical at this point.

How high you want to take your FC level depends on your current CYA level. If CYA is zero, then 15 is a good target. But if CYA is 30 you want to target an FC level of 20.
 
Just to point out another alternative, if the CYA is already high and one wants a faster conversion, one could use a different oxidizer such as sodium percarbonate. We normally don't recommend that because it's more expensive while chlorine alone will do the trick, but if the CYA level is high and the conversion is taking too long, it's an option.

If the CYA is low, like 20 ppm or so, then high FC levels at or higher than that CYA level should work fine, but if the CYA got to 50+ ppm then the sodium percarbonate might be considered. If one goes that route, then the conversion isn't colorful.
 
Just an FYI update ... Taking all into consideration, I have decided to remove some water by backwashing since my pressure was a bit high. I have also taken the 3" pucks out of the system entirely. While doing these things I remembered that I wanted to check how my inlet valve worked so I removed it ... finding out that the pool guy put it back in wrong 2 yrs ago. and the water was not being pulled from the bottom drain/inlet much. if at all. This would explain why there has been a maguarita green color in the deep end. I have since replaced the valve and pulled entirely from the bottom for the first ten minutes or so ... this produced a lot of foam, similar to what was produced when initially shocking the baguanides. I have now set the valve to pull equally from both the skimmer and bottom inlet and am refilling with "clean" (tap) water.I would assume that since the bottom inlet was non functioning I was getting a builup of checmicals in the deep end ... am I wrong?
 
Ok ... now since fixing the valeve and verifying that it was only pulling at best 25% from the bottom (or may have even been plugged), the chemical cocktail that was in the deep end has been circulating approximately 2hrs, the greenish color has disipated greatly and here are my readings. Please note that I have not added a drop of chemical today and the pool has been in direct sunlight for the majority of an 85 degree day.

FC 2
TC 10-12
PH 7.2
TA 160

The only change being an increase in free chlorine ...
Any thoughts?
 
Given the current numbers and using the pool calculator, would it be safe to start hitting it with bleach tonight to start maintaining 15ppm until I receive the test on Tues.? I will still get readings from Leslies as a reference until then.
 
Sure. You don't have to hit any numbers exactly during this phase of the conversion, so you can continue along with imperfect testing for now. Later, when the FC level stays more or less the same overnight, you will need the FAS-DPD test.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.