I don't even know... help raising FC with a SWCG?

l1ltaral1l

Bronze Supporter
Jul 16, 2019
573
Walnutport, PA
My test results should be linked. I thought I was smooth sailing for a while, but then my FC dropped to nothing. I turned up the SWCG (from 30-35% to 50%) and my FC raised slightly (to 0.5ppm). I guess I need to understand how the SWCG works better. I've kept the pump on 24/7 for the past two days. Just turned the SWCG up again to 70%. I thought it wouldn't need to be up this high, especially with the pump on 24/7?

Other factors:
The pool has been heavily used the past week. Not much rain - a pop up shower here and there but nothing substantial.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
It's possible the recent crash of FC from heavy swimming wa too much for the SWG to gain back. Use some liquid chlorine/regular bleach ASAP to increase the FC to 6-8 range. It needs it now. Let it mix well this evening and then yes, do the Overnight Chlorine Loss Test. First confirm there is no algae to worry about, then you can come back to the SWG to see if there is a mechanical issue with it.
 
  • Like
Reactions: l1ltaral1l

Msch99

Gold Supporter
Bronze Supporter
Jun 11, 2018
863
Verona, MO
I usually just add a couple ppm of liquid chlorine and leave SWG set if it is working ok otherwise. 30 minutes Before or after Out.
 

Newdude

Well-known member
Jun 16, 2019
3,772
NY
Thats the not good kind, pretty much all Clorox is out now, but in other countries they still have plain Clorox without all the polymer add ins. With any luck 1 gallon wont hurt.

Also with any luck you'll pass the OCLT and it was just more demand from the heat and high use. Its very possible you caught it in time. From here on out though you would benefit from running with some insurance FC. I saw the 3-5s in your history and that is one day away from the edge at 4ppm loss per day. Too close for my liking and i will gladly waste some FC that i didn't need to protect my honkin backyard investment. Especially this year, if we lose swimming due to a algae breakout it will hurt more than normal.
 
Last edited:

mguzzy

Gold Supporter
Jul 8, 2015
2,041
OV, CA
Once this is under control, would turning the SWCG up before heavy swimming be a good idea?
I do it both ways.. if I know the weather is going to be hot or there is an impending pool party I will crank up the SWG in preparation for the event. But I know it takes time... so I give it a few days to build up. I also keep some chlorine around if I can't plan for it. like a sudden heatwave or like today, my son decided to have a impromptu pool party with his buds.. I'll get the Cl backup with a shot of Chlorine.
 

poolnoobgrandma

Well-known member
Sep 15, 2018
346
Seminole, FL
Same here - This is only our second summer with the SWG, so we are still learning. I keep the chlorine at the high end of the "desireable" range all the time. That way if the SWG isn't "keeping up" I can make the adjustment before it gets bad. I found that as the days get sunnier, longer, and hotter, (and we have more people in the pool) the demand goes up, and I'll need to turn things up (more run time or higher percentage) or I'll start to see real chlorine loss and the pool will start to not be sparkly enough. If I don't stay ahead of it, I'll end up needing to add chlorine to nip potential problems in the bud.

We had a much heavier pool load for 3 days over the weekend. We started at 10ppm before all the festivities, and this morning (pool still sparkly and crystal clear) we are down to 7.5 (no CC). That's before the SWG runs, so I'm going to see what it is this evening, and do an OCLT. If it seems like trouble is brewing, I'll do a "mini-slam" (add chlorine to get it into the teens) and let it drift down.
Sometime last week it just didn't look as clear as I like late in the day, so I ran the pump overnight to add some extra chlorine, and everything has been perfect since.

The main thing is that SWG is NOT "set it and forget it." Weather, bather load, etc., will impact the FC use, and tweaking will be needed.

Now that we are past the solstice, the days will be getting shorter, but hotter. So we'll see what happens. I have learned what sparkly clear water looks like. I do THAT test every day.
 

Dtkokay

Well-known member
Dec 31, 2019
265
Houston, Texas
I've always viewed the SWCG as a device to maintain chlorine level, rather than raise it. I realize it can do that, but I keep liquid chlorine on hand in case I ever need to bump the level higher, or if I know people are coming over to swim.
 
  • Like
Reactions: l1ltaral1l

poolnoobgrandma

Well-known member
Sep 15, 2018
346
Seminole, FL
Well, OCLT was OK, so I sprinkled some cal-hypo in to raise the FC back up to the high end of the preferred level. I'm saving my liquid chlorine for a rainy day (pun intended). I think the bather load and the sunny days just took us down just a bit, and I don't expect our SWG to raise it back up.