Printable View
Thanks for all the info I've read in the past, I just revieved my PS234s and here are the results...
FC - 5
CC - 1
pH - 7.6
Alk - 70
Cal - 320
Cya - 0
Salt - 3200
20,000 gal plaster inground pool / SWG
I know I need to raise the Alk a bit, shock to get rid of the CC, and raise the Cya to maybe... 50?? Not sure i buy into the 80 ppm the SWG book says. Any other sugestions?
The stablizer container is very vague about the amount to add. I just added 2lbs and will check again tommorow.
Thanks, Dave
Hi, Dave,
Sounds like you've got a solid plan.
I'm sorta' with you on the CYA. SWG folks are pretty consistent in their advice to run high levels, tho.
Shock with Clorox and save your SWG cell.
read my reply to CarlD in this thread about my observatons on CYA and SWGs
http://www.poolforum.com/pf2/showthread.php?t=2785
Once you get the CYA in there you probably won't need to shock and will mostg likely need to turn the output on your cell down!
Get your ALK up and then get your pH down afterwards. Keep monitoring the pH and try to keep it as close to 7.2 as possible when you ajust it down. It will rise soon enough on it's own! Try not to let it get above 7.8 (7.6 is a better number to shoot for as your upper limit)
To raise your CYA from 0 to 60 you will need 9.5 lbs for 20000 gal. 60 is the lowest I would recommend you run it with! I have noticed problems with CC in my pool and my customers pools when the CYA is 50 or below with a SWG...don't know why but I've seen it time and again. I know it goes against the accepted info on the forum but I have been seeing this time and again. I suspect it is because of the way the chlorine is introduced into the pool with a SWG. It really isn't the same as dosing manually.
We have a demo SWG cell at work that is a lucite tube with 2 electrode plates in it and a battery for a power source. We put salt water in it and 5 drops of OTO to show customers how the cell generates chlorine. When we press the on button the water in the area around the electrodes immediately turns deep orange to brown showing extremely high chlorine concentratons right around the plates and a much lighter yellow color throughout the water (maybe about 1-2 ppm). this shows how the water is being 'supershocked' right around the electrodes. If we keep the unit on the entire water column in the tube will turn brown in a matter of seconds. I cannot think of any other way of introducing chlorine into a pool that is like this. Perhaps this is why the high CYA levels and lower chlorine levels work with a SWG.
Just a note--stabilizer is going to take closer to a week to fully dissolve and show up. If you add more stabilizer after 2 days, then when it all does dissolve, you will have overshot your target. Give it a week, then re-test for it.
Janet
Wow you guys are good. Thanks for the advice. It makes life so much easier to get clear, sound input and you guys seem to think of everything. Very much appreciated.
You would think the bottle of Cya would tell you to wait a week, or not to put it directly in the skimmer if you have a DE filter and its close to needing backwashing. I wonder why it doesn't come in powder form so it would dissolve quicker. I'm doing the mesh bag trick (with the cya in nylons) and putting the bag in the skimmer. It seems to be dissolving pretty quick, we'll see.
Does Cya harm anything that it may touch? I have the nylons in my extra Pentair Legend cleaner bag, and I let some go to the bottom of the pool on my first attempt, before I read about the slow dissolve time.
Thanks Again... Dave
it won't hurt anything it touches...don't worry about it.