What to do w/chemicals after SWGC activation

grivera

Well-known member
Jul 3, 2007
89
Maryland
#1
My pool was opened on July 2, 2007. At that time, being totally ignorant to this pool business, I purchased various chemicals per the service department's recommendations--the rep. knew the Aquapure swcg would be activateed 1 month later as they were doing the activation, that happened this afternoon. The chemicals I now have are 22 lb. bucket of hypo chlor granules (non stabilized) and about 13 lbs of tri-chlor 3" tablets. The rep. who activated the swcg stated that I should not use the hypo chlor granules for shock because it would eventually damage the swcg cell. Is this true? Will I have any use for the tri-chlor tablets?
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#2
It is time to do some reading. There are at least six numbers that you need to keep in balance. Most of them are fairly easy, but a few, like PH, are likely to move and need to be brought back in line reguarly.

The first step is to get a good test kit, I recommend the TF Test Kit, there is a link in my signature. There are other good options but that one is probably the best value. A good test kit is the best investment in your pool you can make.

Then start reading through some of the Stickies, there is a link in the sub-heading of each page at this site, particuarly the first one, BBB and basic chemistry. You might also want to have a look at the help text for my Pool Calculator which has some good background on the things you will be testing for and what numbers to aim for.

You might have some use for those chemicals. Used in excess either one will cause problems. But there are approriate times to use them. To know when you will need to start by getting the test kit and finding out where your are at right now. The most important number is PH. The paster is going to raise the PH while it cures and you need to keep the PH from getting to high. That one is probably firly time critical, if the PH gets too far out of line there can be serious problems. Hopefully the SWG is working correctly and you don't need to worry about chlorine for a few days, but it would be good to get a quick check on that as well. Hopefully your builder got everything else in line to start with and they can wait.
 

grivera

Well-known member
Jul 3, 2007
89
Maryland
#3
Jasonlion, I posted in the poolschool section cause it seemed like the most appropriate for my topic. I've had the TFP test kit for a couple of weeks. My numbers as of this morning were as follows:

FC- 2.0
CC- 0
TC- 2
PH-7.2
TA-90
CH-240
CYA-50

My Aquapure was just activated today. I'm just hoping that I have use for these expensive chemicals. What do you think?
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#4
Yes, you can make some use of what you have, but it gets tricky to use if efficently because you need to balance the various things each one adds. You could do with more calcium and a little more CYA. Both of which you could get by using what you have. Normal recommendation on CYA is 60-80 for a SWG. To raise CYA by 20 would be 90 oz of trichlor, 11 to 15 trichlor pucks (depending on which size pucks you have). You could do with more calcium, something like 100 to 150 ppm more, particuarly if you want to let TA come down a little. That would take quite a lot of cal-hypo, but then calcium is still going to come up some on it's own because of the plaster curing and it is difficult to say by how much. Further the SWG will be supplying chlorine, all that cal-hypo and trichlor would raise FC quite a bit. So you would need to either turn down the SWG quite a bit or turn it off while using either trichlor or cal-hypo over time to get value out of the chlorine they contain.

I would go for the trichlor, about 90 oz worth, used over time to keep FC at an appropriate level with the SWG off. The acid from the trichlor will also help maintain your PH. 22 lbs of cal-hypo will raise CH by about 66, used over time to maintain FC at appropriate levels that would be one way to get your calcium up.
 

grivera

Well-known member
Jul 3, 2007
89
Maryland
#5
JasonLion, thanks for entertaining my novice questions.

When you say the SWG off, do you mean that it can be powered on, but chlorine production at "0". Once the unit was activated, the sensor was screwed in to the pvc and it began reading salt and temp. Is it ok to use cal hypo and the tri chlor with this sensor screwed in without causing any damage? (prior to activation, there was a PVC plug in the place of the sensor.

Also, this afternoon, my FC was 0. I removed the trichlor yesterday at 4pm per the service reps advice. Today, I set chlorine production at 60% and will check FC tomorrow afternoon. Do I need to begin adding CYA immediately; is the 0 chlorine reading due to the removal of the trichlor tabs? Or will my prior CYA levels hold for a while?

BTW, my salt level this afternoon was 3500 ppm
 

pooladdict

TFP Guide
In The Industry
May 14, 2007
819
New Brunswick Canada
#6
Grivera...I am not sure, but my pool store credited me for what I brought back, and I now have a credit to eat up with Socks and PH Minus, not to mention all the other toys I buy there.
 

grivera

Well-known member
Jul 3, 2007
89
Maryland
#7
Unfortunately, Namco Pool Store has a written policy prohibiting return of unused/unopened chemicals. Like a dumb a**, I didn't read the small print until it was pointed out to me by the store clerk when I attempted to return them.
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#8
Setting the SWG to 0% would be fine. Trichlor etc. won't bother the sensor.

Your levels are fine, not ideal but not way off. You will want to bring up the CYA and the CH but no rush on either one. Do the CYA first. Then figure out where you want TA to be long term, probably 70-80. Then try to figure out what CH level will exactly balance your calcite saturation (my Pool Calculator or the Taylor Watergram will help there) and aim for that. Take your time on the CH and that will let you see how much more CH going to come from plaster curing.
 

The Mermaid Queen

TFP Expert
LifeTime Supporter
Mar 28, 2007
2,522
Northern KY
#11
JasonLion said:
.... You might also want to have a look at the help text for my Pool Calculator which has some good background on the things you will be testing for and what numbers to aim for....
I did not know this page existed!! Is there a link from your calculator page? If so, I cannot find it. That is a lot of good info, and even color-coded to match your calculator! :goodjob:

ETA Oh DUH! I see that each parameter is a link to that page. Never noticed that before!