Intex SWG longer run time not increasing FC much more than normal run time

[fareal]

I've been using my Intex SWG for a month now. The first week or two it seems to have done a better job at increasing FC with shorter run times than it is doing now. Now it seems no matter how long I run it I cannot reach 6 ppm FC.

A month ago with the new pool, new water, new salt, new filter pump SWG, I could run it for 3 to 4 hours and maintain 6ppm FC in the morning. During the day lose a couple ppm, repeat. Now it seems it doesn't matter if I run the combo pump SWG for 4 to 10 hours I'm not reaching 6 ppm. I usually get to 4.5 FC so then by the evening I'm at or below minimum FC, 2 to 3 ppm.

Water is clear. OCLT passes. I lose .5 ppm at night at last OCLT. But I'd like to keep my FC at 6 ppm in the AM. Can't seem to do it. I cleaned my SWG cell a few days ago but it didn't help.

Is this normal? Is an Intex SWG going to work optimal the first week or two with new salt and then settle down like mine has? I see bubbles on the SWG plates every time it's running. Once I checked towards the end of a cycle and there were none but I think I read that's normal when in gets within 30 mins of the end of the run time.

Since increasing run time more than 4 hours seems to do nothing for me I think I'm going to go back to the recommended run time of 3 to 4 hours and see if FC drops below Intex recommend levels and then call them again. Per my last call it seems that's what they want to hear before they take any action.

Or maybe what I'll do is use bleach to get it up to 6 ppm and then go to a 5 hour run time and see if I can maintain.

But I guess the whole point of my post is, shouldn't I be able to increase FC by increasing run time? And then decrease run time to maintain. Or maybe an SWG doesn't work that way and once all my pool water has passed through the system once or twice then SWG won't continue to work the same way? If that is the case then even my thoughts of a 5 hour run time is too long.

Flow rate of my system is 2150 gallons per hour. Sanitizer output is 11 grams per hour which works out to be .6 ppm per hour with my pool.

FC 4
CC 0 to .5
PH 7.5
CH 300
TA 110
CYA 70
Salt 3200

 

[cowboycasey]

You are all over it but your going the wrong way with run time

To get 6FC with the heat and the intex you will probably have to run 14 to 18 hours a day to keep up...

Yes, when it first started the SWG worked a little better than normal, now it has slowed down to normal rate, 11 grams an hour or as you said .6FC per hour we will use .5 for ease..

.5fc x 14 hours = 7 fc

with normal use and loss during the day you need to add more than is being used.. you may need to run 14 to 18 hours to keep up..

1. Bring your FC up to 7 using bleach
2. run pump 14 hours
3. test at normal time (you said morning time you test) and see if you are still at 7FC

I hope this helps

 

[fareal]

Hi cowboycasey, since I'm a pool newbie I am still obsessed with testing. I thought I would have slowed down by now, but with my challenge with the SWG sometimes I'm testing multiple times per day just to try to understand what's going on.

Yesterday morning I was at 4 FC. Normally if I noticed that in the morning I would have ran the system again in the morning since my target is 5 to 6. But I didn't do that yesterday, I let it be. At 10pm when I got home I tested again and I was at 2 FC. At that time, I added bleach for the first time (30 to 32 oz of 8.25) and this morning I'm at 6 FC. I'll test again tonight and then set the run time on the system based upon your response.

Wow, so 14 to 18 hours? Even if I'm at 4 ppm at the end of the day and only want to be at 6 ppm by the morning?

 

[cowboycasey]

yep, do a set amount of time daily, then test at the same time.. I test at night and make sure I am at 7FC or above..

I run from 0630AM to 1830 (630PM) at 75% SWG Mine is way oversized

so, start at 12 hours a day, test at night, if at or above 6 keep it the same..

if below 6 add run time..

if above 9 take time away

 

[fareal]

Thanks cowboy. Max run time (without manually running a second time each day) of my Intex SWG is 12 hours. This seems to be just enough (mid So Cal summer) to keep my 16x48 round Intex between 3 and 6 ppm FC throughout the day.

 

[fareal]

Now only having to run 10 hours per day. I may have found some organic matter on the inside edges of the Intex liner at the bottom of the pool where there are overlaps. I couldn't see anything, no green, but some parts of it felt a little more slick than it should. Plus some extra dirt and tree matter in there. I brushed it out a few times. Now I'm actually testing 0 CC instead of .5 CC (1 drop).

It was that and/or temperature drop from 100's and high 90's to low 90's now.