Where has all the salt gone?

[VinnyinNJ]

I'm a salt newbie! I used my SWG 3 days last season before we closed the pool just to see if it worked and this year I haven't used it yet - all done by LC so far. I cracked open the last bottle this weekend and figured lets get the pool ready for the SWG. I tested the salt using the Taylor salt water kit today and the first test indicated I had 1200 PPM and the second test indicated I had 1400 PPM ... the last time I tested for salt was in May and after fluctuating a couple of days it settled around 3000 PPM. Other than rain and possibly the pool discharging water from the skimmer no other water was added/removed - the pool is higher due to the rain but not enough to dilute the salt 1600 PPM.

Is it possible we lost that much salt due to rain? I was expecting to add 40 lbs of salt to raise it slightly due to dilution and/or water loss which I did but that's only 350 ish PPM, I have another 5-6 bags to go? This seems odd to me!

 

[HermanTX]

The Taylor salt test has a +/- 200ppm error as you have found in your own testing. So that is fine. Do another test and believe in your test results. Hard to pinpoint what happened over many months but dilution is a big factor.
Also, ensure you are circulating your water before you test. Maybe even brush some and then let it circulate 30 mins or so before taking a sample.

 

[VinnyinNJ]

The Taylor salt test has a +/- 200ppm error as you have found in your own testing. So that is fine. Do another test and believe in your test results. Hard to pinpoint what happened over many months but dilution is a big factor.
Also, ensure you are circulating your water before you test. Maybe even brush some and then let it circulate 30 mins or so before taking a sample.

Thanks @HermanTX! The readings were before I added the salt and I'm going to wait at least 24 hours before taking another reading to see what 40 lbs of salt gave me (expecting to see 1600 to 1800). I did find my pump off due the timer's "off" tab had moved but I would think that at this point still or moving water shouldn't make that big of a difference since the salt from May is thoroughly mixed, would the pool not have the same amount of salt throughout the pool (like hotter water rising to the top)?

So far every time I've tested salt I have found there is an error which I'm OK with and understand the drops/testing is not 100% uniform. Losing this much salt surprised me.

 

[generessler]

Hi. I've been assured by the chemistry experts here (and I believe them) that salt concentration doesn't go down by itself. The only explanations are 1) test error and 2) dilution with less salty water. If you have any kind of auto-leveler, you can be losing salt due to rain causing overflow or a slow leak causing a corresponding draw on fill water. Otherwise it could be the test reagents are out of whack; maybe froze or got too hot or just too old? If it's reagents, best get fresh ones before trusting them to add salt.

 

[VinnyinNJ]

Hi. I've been assured by the chemistry experts here (and I believe them) that salt concentration doesn't go down by itself. The only explanations are 1) test error and 2) dilution with less salty water. If you have any kind of auto-leveler, you can be losing salt due to rain causing overflow or a slow leak causing a corresponding draw on fill water. Otherwise it could be the test reagents are out of whack; maybe froze or got too hot or just too old? If it's reagents, best get fresh ones before trusting them to add salt.

Thanks for the reply @generessler!

I know that salt doesn't evaporate so I was totally surprised by my result. The test itself is fairly easy and not exact and I repeated it to make sure I didn't screw up. When I stuck my hands in the water the water had stratified with hotter water above the other water, my pump wasn't on so I looked at the timer and the off tab was hours away from where it was supposed to be. Is it possible that the water stratified with the salt, I don't know.

As far as the reagents - they are within date, are kept in my basement so no heat/freeze, are basically in the dark being in the basement and stored in its salt kit box and was bought from tftestkits so all should be good with them. They may be bad but at this point I'm not pointing my finger at them.

The only 2 things I can think of was dilution and/or stratification and hopefully my pump stays running until I get home tonight I'll get rid of one of those. Yes, reagents bad can be the issue but I've never had bad reagents before.

It's an AG pool so no auto fill, if it tests the same I'll say dilution for now. It could be more water came out of our pool than I anticipated from the rain.

Thanks again!

 

[duraleigh]

I think it is simply rain and fill water that caused this dilution. Trust your testing!
Circulate water thoroughly and then do one more test. I'll bet you find the same result. Add salt accordingly

 

[VinnyinNJ]

Thanks @duraleigh!

i didn't expect that much salt gone from simple rain water, I'mtrusting the test. Plan on getting bags of salt to have so I can add and get the SWG ready!

 

[VinnyinNJ]

I appreciate the help you have given me!

Was expecting a higher salt level than I got. Pool is maybe 500 gallons more (about 2 inches higher on skimmer) and didn't think it oozed much water out of the skimmer from the rain.

I'll be testing tonight to see, using pool math for quantity to add and test again in 24/48 hours.

Thanks for your help!

Vinny

 

[JoyfulNoise]

When it rains, the pure rain water is less dense than the salt water in the pool (TDS of rain water is practically zero whereas your pool’s TDS is over 4000ppm). It will accumulate at the surface and sit there. Mixing pure water and brackish water takes a lot of time.

I suggest you run your pump for at least 24 hours after any rain and vigorously brush the pool sides down. Mix the water as thoroughly as you can. Then test.

 

[SecoSteve]

I'm in the Northeast as well as you and I have had to add two bags of salt already this season. The Spring/early Summer was dry, so I had to fill quite a bit(had a lot of evaporation). Then, we got massive rains which diluted the salt water quite a bit. I'm sure you lost a lot of water through your skimmer lid that you didn't realize was happening. I'm back down to my lower threshold of salt again, so pretty soon I'll be on my third bag.

 

[VinnyinNJ]

After adding the 40 lbs of salt yesterday I had the pump run 24 hours, went in and brushed the walls and floors (been meaning to do that anyway) and I got a reading of 1600. I put in about 3 1/2 bags of salt, made sure it was dissolved and have the pump running again for another 24 hours. I'll test tomorrow and again on Friday night to see where the readings go. BTW, I used the Diamond Crystal Solar salt and it dissolved quickly and it was clean!

I will attribute the lost salt to the rain and dilution.

Thanks to all of you for your knowledge and help!

 

[Darin]

I will attribute the lost salt to the rain and dilution.

Realize that the only place it can go is splash out or out the waste valve from backwash. There is no other way to lose salt. Kinda like maintaining CYA during swim season, except you dont loose salt over winter.

 

[VinnyinNJ]

Realize that the only place it can go is splash out or out the waste valve from backwash. There is no other way to lose salt. Kinda like maintaining CYA during swim season, except you dont loose salt over winter.

Thanks for the response!

No splash out from us and I haven't backwashed but once and didn't refill. I'm thinking it was from the rain, it got to the top of the skimmer and it just oozed out more than I thought. New skimmer has a lid that is attached, my last skimmer lid just sat on top and would pop off all the time.

I expected to see about 2000 PPM not 1200 or 1400 so it took me by surprise. CYA is the next thing I may look at but with a solar cover on I'm not getting a lot of chlorine burn up. I've been keeping FC above 6 and using the LC I bought at startup in May.i just opened the last bottle and figured it was time to get ready for the SWG.

 

[Darin]

.i just opened the last bottle and figured it was time to get ready for the SWG.

Just a note from experience, even though you have a SWG you should keep a bottle or two on hand for that oops moment.

 

[VinnyinNJ]

Just a note from experience, even though you have a SWG you should keep a bottle or two on hand for that oops moment.

Great idea, thanks!

 

[VinnyinNJ]

Talk me off the ledge!

I added 140 lbs of salt on Wednesday to a reading of 1600 PPM, I measured it last night and it was 1800, we had some rain late in the day and found my pump had turned off so I attributed it to water not mixing. I went out this morning and apparently it had rained last night (I don't know how much) and now my reading is at 2200 PPM. It's supposed to be rainy all day (all week!) so I doubt I'll get a true reading. So far this season I added an awful lot of salt, 3 bags at startup - have to when adding water at startup, understand. Lost salt due to rain/dilution last Wednesday- OK. I should have had about 2600-2800 PPM salt after adding 140 lbs - could I have lost 400-600 PPM (give or take) from rain so far in a few days?

I honestly didn't expect to be adding this much salt to the pool. I expected some adding but not 100's of lbs for a smallish (13.5K gallon) pool. If my reading is correct and based what I remember what Pool Math said - I need to add 2 more bags of salt to get to about 3000 PPM. Lugging 2 gallons of chlorine is much easier than 4 - 40 lb bags of salt. I paid $22 for 4 gallons of chlorine vs $9 a bag for salt, and $1000 for the SWG. I can probably get 4 more gallons of LC at Walmart at under $6 each and finish out the season.

I have had water oozing out of my skimmer for a while (out of the top cover not around the skimmer so all good). I need to vacuum the pool and will backwash after that to stop the oozing. I guess it'll become more stable if I'm not "losing" water? If it's not thunder storming today I'll get out there and backwash the filter to lose some water. This part of pool ownership is not going well so far!

At this point it is not economical and/or easy or maybe I'm doing it wrong! HELP!

 

[ajw22]

We have got lots of rain this year in NJ to dilute pools. If you have not needed to drain your overflowing pool then you have a lot more water “oozing” over your skimmer then you think you do.

I probably need to drain my overflowing pool today for the third time this year due to the rain. I hate dumping the good chemicals. I may try to crank up my heater to evaporate some water but it has been so warm and humid that has not helped much so far.

Just blame the added cost on Mother Nature and be glad your roof is not leaking.

 

[VinnyinNJ]

We have got lots of rain this year in NJ to dilute pools. If you have not needed to drain your overflowing pool then you have a lot more water “oozing” over your skimmer then you think you do.

I probably need to drain my overflowing pool today for the third time this year due to the rain. I hate dumping the good chemicals. I may try to crank up my heater to evaporate some water but it has been so warm and humid that has not helped much so far.

Just blame the added cost on Mother Nature and be glad your roof is not leaking.

So I guess we're just victims of climate change here in NJ!

Thanks for talking me off the ledge!

 

[JoyfulNoise]

Seems odd that you’re losing so much salt honestly. Rain water should float on brackish pool water.

Do you have a top drain that keeps the level set?

 

[VinnyinNJ]

Seems odd that you’re losing so much salt honestly. Rain water should float on brackish pool water.

Do you have a top drain that keeps the level set?

No, it's an AG pool and the only drain is the skimmer oozing. This skimmer kind of locks into place vs our old skimmer which just sat on top, both were/are Hayward. My water is sitting at the top of the skimmer opening and when it's not raining I see water dripping from the bottom of the piping at the skimmer and it is at the top of the finger hole. Other than the oozing I am not losing water and haven't had to fill the pool since startup. I have been waiting to vacuum the pool and backwash the filter (filter is sitting at 17 PSI which is the same as startup).

Last night and this morning I attributed both readings to possible non mixing of water types, not sure how much mixing is needed. Could my reagents be bad? Yes they could but they sit in a dark, coolish basement inside their blue Taylor box. I bought them last July from tftestkit and their dates are OK, one is in 2024 and one is 8/2023. I don't think reagents go bad quickly after their "use by" date.

This is the first year of ever using salt, I want to develop the knowledge to feel confident that having a SWG was/is worth it. I'm not new to testing the TFP way, been doing it forever but this has thrown me for a loop.

What everyone is saying that there was more rainwater than I expected is probably true. I expected my first salt reading that I started this thread to be around 2000 not 1200 or 1400. I expected this morning's reading to be 2600 or 2800 not 2200. But again I have no clue how much rain fell and water oozed out.