rogue salt level

[morning dipper]

Hi all - still muddling along with dip tests and your help......:grin:

Would appreciate some 'gut feeling' 'seat of the pants' type help (FYI no proper test kits in this part of the world!)

FC +/- 7 pH 7.3 today CYA 60 - from dip strips....so +/-

Pool up to 22°c (73F) and clear but not crystal. Slightest of green tinge to water (beige tiles) and very local algae bloom on walls. Polaris bag green!

Filter and SWG running 7hrs/24. SWG produces 24g/hr....or should.

Under 'normal circumstances how long should SWG need to run?

Have dipped pool for salt (Nacl) and it gives 0.8g/l...very low. Added 1 g/l salt and SWG cut out salt too high! Called manufacturer and he said lower salt....I did, back to +/- 0.8g/l and running again.

What else can make salt readings unreliable? and at low levels of Nacl will SWG actually produce the cl it says?

Your thoughts much appreciated.

(thx to CC and comments on another board.....above also on 'lost in france' on testing/balancing water)

 

[YippeeSkippy]

My SWG sits at 3200-3400ppm which it is designed for. I test with an independent drop salt test kit and I'm right on the money yet my SWG tells me I have *high salt level*. Thankfully it still chugs along producing chlorine.

My motto is : if the SWG is happy, I'm happy.

What % are you running the SWG during the 7 hours you run per day? Can you increase that? A fast way to determine if your SWG is indeed producing is to collect some water *immediately from the return* and test its chlorine level. Then test the rest of the pool from elsewhere and compare.

Since you have algae you can also add liquid chlorine to the water to supplement your SWG if necessary.

 

[FattyLumpkin]

.... I test with an independent drop salt test kit and I'm right on the money yet my SWG tells me I have *high salt level*...

Unrelated, but Yippee, may I ask what drop test you are using? I am relying on my EasyTouch / IC-40 and strips to "average" a level... not exactly precise.

 

[YippeeSkippy]

Taylor's K-1766 Salt Test kit- TFTestkits.net

 

[ping]

Once your pool is clear of all algae and passes the SLAM process, the SWG has more than enough ability to keep a balanced pool clear.

With my calculations I get that your SWG can make 15ppm of FC each day in your 10,000 gallon pool. Most pools use between 2-4ppm of FC each day during the summer if they are algae free and balanced per TFP recommendations. Right now your SWG can't make enough chlorine in a day to kill off all the algae so the pool needs the SLAM process completed.

Some people run their SWG's at a lower output percentage with longer pump run times to get more filtering, while others have short run times and have a high SWG output percentage. How you choose to run yours is up to you.

Most SWG's in the USA need around 3000 to 4000ppm of salt in the water to operate at peak performance. Outside of the USA, SWG's tend to need more salt, but I'm not sure what your SWG requires.

 

[morning dipper]

Thank you all for your input.

What % are you running the SWG during the 7 hours you run per day? Can you increase that? A fast way to determine if your SWG is indeed producing is to collect some water *immediately from the return* and test its chlorine level. Then test the rest of the pool from elsewhere and compare.

Presently SWG runs off main pump timer, and runs at full capacity, ie 100% production. SWG can only run at 100%, but either as slave to main pump or with its own water T° controlled timer.....as long as main p/p gives it enough time. I have settled on a 7 hr manual cycle as I seemed to have enough FC....!?

@ ping

With my calculations I get that your SWG can make 15ppm of FC each day in your 10,000 gallon pool. Most pools use between 2-4ppm of FC each day during the summer if they are algae free and balanced per TFP recommendations. Right now your SWG can't make enough chlorine in a day to kill off all the algae so the pool needs the SLAM process completed.

I slammed successfully a few months ago (or as best I could with limited tests) so are you suggesting I need to slam again?

(If I do need to slam again - and lets assume general chem. balance is OK - what have I got wrong these past months to need slamming a 2nd time?)

If I run SWG 24/24 for a few days is that going to be enough.....or is that a how long is my piece of string type question?


SWG manufacturer wants about 3500 ppm of salt (at 25°C)......I am running at 1000 ppm (1g/l) , if I raise the salt level SWG cuts out!

Thanks for reading and appreciate your patience.

 

[morning dipper]

A fast way to determine if your SWG is indeed producing is to collect some water *immediately from the return* and test its chlorine level. Then test the rest of the pool from elsewhere and compare.

Mmmmmmm.......just checked and found no difference between the readings on my Aquachek color dippers!!!! (SWG was producing, not on rest cycle).

 

[ping]

Good luck seeing any difference with test strips. You are in a difficult situation as you can't tell if you have completed the SLAM process due to a lack of being able to do an OCLT. Our method to eliminate all of the algae requires a FAS/DPD test for FC and without that test you will always be guessing if you completed the SLAM or not. A clear looking pool is only 1 part of the process.

Why do you need to SLAM, you have visible algae in the pool.

SWG's do not add enough chlorine for a SLAM. To kill algae you have to add enough chlorine to reach shock level for the CYA level quickly, and you have to maintain the FC at level until all three criteria are met for the SLAM.

 

[morning dipper]

Thanks ping for answereing my queries.

MD

 

[morning dipper]

Why do you need to SLAM, you have visible algae in the pool.

Is this a pool fundamantal? Once algae is visible you have no choice but to SLAM?

Once slammed successfully what is a primary pool condition for new algae appearance? Low CC?

 

[pooldv]

Chlorine sanitized the pool and kills algae. Chlorine level is set based on CYA level and the [FC/CYA][/FC/CYA]. Always keep FC above minimum to keep the pool sanitary and algae free.

 

[domct203]

Is this a pool fundamantal? Once algae is visible you have no choice but to SLAM?

Once slammed successfully what is a primary pool condition for new algae appearance? Low CC?

Yes, the proven and reliable process to kill algae is to SLAM, unfortunately you cannot perform the OCLT to verify that all the algae is indeed eliminated.

When your FC goes below 7.5% of your CYA level algae can grow, and can multiply fast enough to overtake the FC level. The remedy is a controlled & sustained increase in sanitizer (chlorine) until the water is clean.

Dom