Shall I drain water after adding 6 lb Dry Acid to 2.7K gal saltwater pool?

Jump to latest Follow Reply
Stacy-MissionViejo

Stacy-MissionViejo

Member
Jun 23, 2024
23
Mission Viejo, CA
Hi there,
Happy to find out about this community. My husband and I just bought our first house with a 1.8K gal saltwater pool combined with 0.9K spa.
We are complete newbies to pool maintenance. When we moved in, pool water TA was around 280 ppm and pH was above 8.4.
During the last week, we gradually added 6lb of Dry Acid/Sodium Bisulfate (pH decreased to 7.8 and TA is around 140 ppm) to only realize that Dry Acid is a no-go for saltwater generators and concrete pools.
We need advice on whether this concentration of sulfate ions is dangerous for pool equipment and whether we need to drain the pool. Or this concentration is fine to leave if we won't use dry acid anymore and will switch to MA?

Current chemical levels:
- pH = 7.8
- TA 140 ppm
- FC = TC = 3 ppm
- CYA less than 30 ppm (didn't address this yet)
- CH per Tylor liquid test reads around 310 ppm (how blue the sample should become after adding reagent: dark blue or just change the tint from violet to blue?), at the same time TH per AquaCheck test stripes is around 1,000 ppm or higher

Other info: there are white flakes in the pool, they are of small size, they lay on the floor until you disturb the water, not a huge but noticeable amount of them

Thank you for sharing your expertise,
Stacy
 
Last edited:
The sulfates are likely causing the flakes as they cause scale in the cell. Are the flakes sharp?

What are your water rates? At 2700 gallons, I'd be inclined to replace all the water. Read no Drain water exchange here:

Draining - Further Reading

www.troublefreepool.com www.troublefreepool.com
 
Welcome to TFP! :wave:

Your combined pool/spa is about 19,000 gallons total.
Most likely, 6 pounds of dry acid didn't do much harm. Continued use of dry acid will though.

How are you testing your water?
Test Kits Compared

Have a look thru Pool Care Basics and a few of our YouTube videos.

Tekk us more about your pool and its equipment by updating your signarure with equipment manufacrurers and model numbers. Add your test kit info as well.
 
Sorry for the confusion with the pool size in the signature. It is of a smaller size: 1,800 gals of water in the pool and 900 gals in the spa. As far as I understand, the same pump and SWG are used for both, so water is eventually mixed.
I don't know the water rates yet as I haven't received any bills. May need to contact the provider once they open tomorrow.
The particles in the water look like they have sharp edges, but I have problems catching and sensing them even from a cup as they are pretty small.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Another issue I have with this pool is these build-ups between tiles above water level. I would appreciate any ideas on what they are, how to treat them, and whether I should address them before the draining. They are hard to touch.
 

Attachments

  • PXL_20240623_233529929.jpg
    PXL_20240623_233529929.jpg
    509.1 KB · Views: 5
  • PXL_20240623_233511657.jpg
    PXL_20240623_233511657.jpg
    532.4 KB · Views: 5
To avoid further confusion, please change your signature to indicate
1,800 gallon pool and 900 gallon spa instead of 1.8k and 0.9k.

Post a couple pics of the pool/spa and the equipment pad.
 
Some missing equipment and chemicals are coming, and hopefully, I can exchange the pool water today.
I planned to exchange the full amount of water using a no-drain method, test and balance it. I would appreciate the community's help with some questions. Doing my own research, but my head is spinning from all the info to consume fast, and I have little confidence in my own conclusions.

1. I did end up with a noticeable amount of scaling on the pool's surfaces during the last two days. Shall I still change the water, balance it, and hope that some build-up dissolute/soften up with appropriately balanced water?
Or do I need to fully drain the pool and attempt to clear surfaces first? Scary to make it even worse if the pool pops up.
2. Can I help with something while waiting for the missing parts, especially if I end up getting some missing items only tomorrow? Brushing?
3. What is the right sequence of actions to balance the water after refill? As per the water report, my fill water is expected at pH 8.5, TA 84 ppm, and CH 160 ppm.
Do I need to address pH first, then add salt and CYA? Can I just turn on SWG or need to add liquid chlorine first? Do I need to buy and use a calcium increaser considering the anticipated CH of 160 ppm in the refill water?
4. My water company requires discharging to the drain line? How does this look? I have a clean-out under the sink in the kitchen, is that where the water should go? Or may that be smth else on the property?
 
Last edited:
Stacy-MissionViejo said:
1. I did end up with a noticeable amount of scaling on the pool's surfaces during the last two days. Shall I still change the water, balance it, and hope that some build-up dissolute/soften up with appropriately balanced water?
Or do I need to fully drain the pool and attempt to clear surfaces first? Scary to make it even worse if the pool pops up.
Click to expand...
Exchange the water, then we work on the scale.
Stacy-MissionViejo said:
2. Can I help with something while waiting for the missing parts, especially if I end up getting some missing items only tomorrow? Brushing?
Click to expand...
Not much to do, you can brush...
Stacy-MissionViejo said:
3. What is the right sequence of actions to balance the water after refill? As per the water report, my fill water is expected at pH 8.5, TA 84 ppm, and CH 160 ppm.
Do I need to address pH first, then add salt and CYA? Can I just turn on SWG or need to add liquid chlorine first? Do I need to buy and use a calcium increaser considering the anticipated CH of 160 ppm in the refill water?
Click to expand...
Add enough dry chlorine stabilizer to raise your CYA to 30. Use pool math. Link-->PoolMath

Put CYA in a sock, tie it off, and hang it at least 6" out in front of a return, like a carrot on a stick. After about 30 minutes you can start squeezing it if you want. May take several sock fulls to get 30ppm. Just reload the sock(s). If you don't have CYA add 8oz of liquid chlorine per day until you have some.

After the sock hits the pool, raise your FC to the top end of the target range for a CYA of 30. Use liquid chlorine. Use this to determine the FC range for a CYA of 30....Link-->FC/CYA Levels
Test and add liquid chlorine daily to keep yourself in range. If you have to add more (above range) so you stay in range when you test, do that. It might be wise to check a few times a day and re-add chlorine until the CYA shows up on the test, just to give you practice and try to stave off any algae that may be lurking.

Test the CYA 24-48 hours after it is all dissolved. When it reads at least 30, do an OCLT. Link-->Overnight Chlorine Loss Test If you fail OCLT, report back and we will take the right action.

Lower your pH in .4 increments with muriatic acid. Make the addition, test again in 30 minutes. Continue to lower in .4 increments until your pH gets to 7.8.

Which salt generator do you have? Typical recommendation is 3000-4000ppm. Look up in the manual the salt level required for your SWCG. Use pool math to figure out how much to add to get to your target from 0. Add 3/4th of the recommendation, keep the pump running, wait 24 hours, and retest. Creep up on your target with the last 1/4 of the recommendation. Leave the SWCG off until you get the salt level up.

You can do all these additions together. Put the CYA in, dose FC, wait about 15 minutes, then you can start the acid additions. Just always wait about 15 minutes between chlorine and acid, and you can add salt at the same time.

You can add the CH increaser 30 minutes after you have made your pH adjustments.

When your salt is in range, fire up the cell. You now about how much FC your pool has been using because you have been manually dosing. Set your pump run time and % output to be a bit higher output than you have been using with liquid chlorine. If you have been adding about 4FC daily in liquid, set it up to add 5FC daily with run time and % output. Then just adjust run times and output until your FC stays in range. Use pool math to help you with run times and % output to give you the right FC addition.

After all this is done, and your cell is making chlorine, AND you have passed an OCLT, then you can raise your CYA again. I would not go higher than 60 until you dial in your SWCG and can keep your FC in range. Same basic principle. Add 20ppm of CYA, raise your FC with liquid, and turn up your runtime or % output for the NEW FC range for CYA of 60. Again, this is your friend...Link-->FC/CYA Levels

Only after you are comfortable with maintaining the pool, then you can raise your CYA to 70 or 80. If you go there too fast, can't maintain FC, and have to clear the pool of algae, it is much harder...that is why the recommendation to keep CYA a bit lower until you can manage your pool.
 

Enjoying this content?

Support TFP with a donation.

Give Support
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply