CYA and other chemicals after new plaster

Jump to latest Follow Reply
30mins is fine for acid. Just give it a little extra mixing help with your wall brush.

Sorry, no vacuuming or robots, just brushing. The vacuuming and robots will potentially scuff and damage the fresh plaster. Sorry, but PB was correct this time. Your plaster is fresh, new and delicate. Treat it with care.


Sent from my iPhone using Tapatalk
 
I added bleach tonight and tested 30 minutes later. Got FC of 5.5. I also added acid after that and will test PH shortly. I'm planning to test FC again early tomorrow morning and will post those results to see how much I lost overnight. I'll also pick up more baking soda tomorrow morning so I can add that tomorrow. Thanks again.
 
Ok, as I mentioned above, I added bleach last night (Sunday) at 10:30pm and tested an FC of 5.5. I tested again this morning at 7:00am and got 3.5. Is this possibly a normal loss overnight, or do I have some biological problem?

Also, I added some acid last night and tested this morning - somehow I'm still over 8.2 on the PH. I added some more acid this morning before I left for work and will test as soon as I get home this afternoon. I guess the problem is that I don't know how far above 8.2 my PH actually was...

Thoughts?
 
lvrpl said:
Ok, as I mentioned above, I added bleach last night (Sunday) at 10:30pm and tested an FC of 5.5. I tested again this morning at 7:00am and got 3.5. Is this possibly a normal loss overnight, or do I have some biological problem?

Also, I added some acid last night and tested this morning - somehow I'm still over 8.2 on the PH. I added some more acid this morning before I left for work and will test as soon as I get home this afternoon. I guess the problem is that I don't know how far above 8.2 my PH actually was...

Thoughts?
Click to expand...

Well, a 2ppm overnight chlorine loss is not good; it should be less than 1ppm preferably 0ppm. You likely have some algae/organic/biological issues since you went almost two days in the beginning with no FC additions. I'm loathe to recommend a SLAM on top of trying to do a bicarb startup. Perhaps the experts can weigh in on it. You could try raising your FC up to 10ppm tonight after the sun goes down and see what your overnight loss is in the morning.

As for acid and lowering your pH, yes it is going to take some effort there. Your TA is high so its going to take more acid to get it right. Just keep adding, testing and reducing as necessary. Slow and steady wins the race, you don't want to overshoot. Once you get the pH down to 7.6, then you can add in the baking soda to take up the TA. DO NOT ADD THE BAKING SODA BEFORE YOUR pH IS ADJUSTED. You want to get your pH correct first as the increase in TA later on will make lowering the pH difficult.

- - - Updated - - -

From PoolSchool -

Startup Procedures
These rules apply for any start-up technique.
DO NOT SWIM DURING THE BREAK IN PERIOD!
Turn off the heater and leave it off for at least 3 weeks after filling. If practical, bypass the heater during this period.
Fill the pool. The pool should be filled as quickly as possible, without stopping. Use multiple hoses if possible. Do not allow water from the hose to spray directly onto the fresh plaster.
When the pool is full, add a startup dose of sequestrant.
Brush the entire pool at least once a day for the first week and at least once a week for the rest of the first month, more often is better. Make sure to brush the entire plaster surface. Brush from the top of the walls down and from the shallow to the deep end to knock off any loose plaster dust.
[size=+2]Do not SLAM (or shock) the pool during the first 30 days.[/size]
If you have a SWG, do NOT add salt, or turn on the SWG, until 30 days after the plaster was applied.
Do not use any automated cleaning system, buit-in or robotic, during the first three weeks.
Did I mention, NO SWIMMING DURING THE BREAK IN PERIOD!
Click to expand...
 
Ok, thanks for the input. I'll work on getting the PH to 7.6 steadily before doing any additional baking soda.

As for the FC problem, I'll get it up to 10ppm tonight as you suggested and then see how much I lose overnight. If I do have an algae/organic/biological issue, is my best course of action going to be to manage FC levels closely day-to-day (and likely a few times each day) to keep my FC level up until I hit 30 days on the new plaster, and then at that point SLAM? Or is there some other option?

Thanks again.
 
What did you target for your CYA? Try measuring it again today when you get home.

Yeah, as for FC, you're just going to have to try to manage it better for the next 30 days and keep it, as best you can, at the high end of your FC/CYA range. Keep the brushing up as best you can and make sure you keep an eye on your filter pressure. You'll definitely want to keep it clean and running optimally.

- - - Updated - - -

DO you have extra DE on hand for when you backwash the filter?
 
I targeted 40 for CYA. I can try to measure it again today, but will it even show up yet? I was applied about 36 hours ago, and not quite all of it has even finished dissolving in the sock (and I've been squeezing the sock a couple of times a day to help it along).

I do have DE for backwashes. The builder did a backwash on the first or second day (I forget which). I intend to take the filter apart and hose it down this weekend as I'm not sure how clean or dirty it really was when we started. I think the previous owners neglected most of the routine maintenance.

Also, at what point can we swim in it? My 2-year-old keeps looking at his new pool longingly from the window, poor kid :)
 
lvrpl said:
I targeted 40 for CYA. I can try to measure it again today, but will it even show up yet? I was applied about 36 hours ago, and not quite all of it has even finished dissolving in the sock (and I've been squeezing the sock a couple of times a day to help it along).

I do have DE for backwashes. The builder did a backwash on the first or second day (I forget which). I intend to take the filter apart and hose it down this weekend as I'm not sure how clean or dirty it really was when we started. I think the previous owners neglected most of the routine maintenance.

Also, at what point can we swim in it? My 2-year-old keeps looking at his new pool longingly from the window, poor kid :)
Click to expand...

OK, if you still have CYA in the sock then somebody out there to manage it until it is all dissolved. I usually get it all dissolved in a day when I have to add it.

Wow, ok, if you do not know the condition of the filter, then it should have been torn down, cleaned and recharged. Expect to spend several hours doing it. It's not to hard to figure it out, but cleaning out old (possibly REALLY old DE), can take a while. Be careful handling the grids and be sure to inspect the polymer mesh that covers the grids for integrity. When you wash off all the old DE, make sure you use a spray attachment to your hose and don't hit it too hard.

Sorry, but as the startup procedure says, NO SWIMMING for the first 30 days. Also, if you do have an algae bloom, then you're going to need to clean that up as well with a SLAM. Sorry, but you've got a long road ahead of you to get your pool started properly.
 
JoyfulNoise said:
Wow, ok, if you do not know the condition of the filter, then it should have been torn down, cleaned and recharged. Expect to spend several hours doing it. It's to hard to figure it out, but cleaning out old (possibly REALLY old DE), can take a while. Be careful handling the grids and be sure to inspect the polymer mesh that covers the grids for integrity. When you wash off all the old DE, make sure you use a spray attachment to your hose and don't hit it too hard.
Click to expand...

Ya, I realize that now...my builder said he'd take care of the startup, so I just assumed he'd whatever needed to be done. I've since realized that his approach to startup and pool chemistry is a bit haphazard so that's why I'm taking over now instead of in a few weeks. And this is all new to me, so I'm sort of learning in parallel...

JoyfulNoise said:
Sorry, but as the startup procedure says, NO SWIMMING for the first 30 days. Also, if you do have an algae bloom, then you're going to need to clean that up as well with a SLAM. Sorry, but you've got a long road ahead of you to get your pool started properly.
Click to expand...

Gotcha, no problem. I saw where the startup guidelines say no swimming, but it looks like it just called out no swimming during the "break in period" - it wasn't totally clear to me that the break in period is 30 days, thanks for clearing that up. On a sidenote, my builder said we should be able to swim early this week - again, he did great plaster and tile work, I just wouldn't recommend him for startup to anyone knowing what I'm learning now.
 
My biggest concern about swimming is not the plaster startup (although some might find the high pH irritating) but the cleanliness of the water. You do not want to swim in water that is not sanitary. And you can't be 100% sure your water is clean right now given the history.

And I agree about the PB - they are often very good craftsman and know their craft well (plastering & tile) but I would not trust them on chemistry. Many don't know anything about water chemistry and only add chemicals based on anecdote and past beliefs, not on science.


Sent from my iPhone using Tapatalk
 

Enjoying this content?

Support TFP with a donation.

Give Support
Makes total sense, thanks. We'll definitely hold off on the swimming until we've got everything with the water in order. I'll post my FC and PH results later today. And I should hold off on the CYA test for a couple more days?
 
Just remember that if you raise your FC above 10ppm, you can't accurately measure pH. So get all of your pH adjustments done first.


Sent from my iPhone using Tapatalk
 
Ok, a little bad news...I got home this evening and tested, and FC had dropped to 0 and PH is still above 8.2.

I just added enough bleach to take FC up to 7 and am adding acid again now. I'll test again before going to sleep and make sure FC is at 7, and I'll try to keep it there. I'll also work on bringing the PH down slowly.
 
Once you get that sock of CYA dissolved, give it a day and measure your CYA.

Also, are you running the pump 24/7? You need to keep the circulation going and brush as much as you can. Unfortunately you've got something in the water eating up your chlorine and I'm pretty sure it's a nascent algae bloom. Try to keep your FC up as best you can while you work on the pH and TA.


Sent from my iPhone using Tapatalk
 
I took the sock out tonight so I'll measure the CYA on Wednesday. Yes, I'm running the pump 24/7. And we're brushing twice a day now.

I measured the FC tonight at 11:00pm and got 6.5 (I added a good measure of bleach earlier tonight around 6:30pm). I'll measure again first thing tomorrow morning and see how much I lost overnight again.

I also measured PH just now and am still getting over 8.2....that means that I've put ~90 oz of muriatic acid in over the last 24 hours and am still over 8.2. Should I be concerned? I feel like I should be concerned. The builder put ~2.5 gallons of MA in on the first day - that's the only other MA that's been added since we filled the pool last Wednesday. Either way, I'll keep adding MA steadily until I see that number come down.
 
I'm not at all surprised by the amount you're adding. It's a fresh plaster start so there's a lot of alkalinity to overcome before the pH starts to drop. You're doing the right thing though - adding slowly and measuring. Keep it up, you'll get there. As the plaster cures over the next few weeks, you'll still be adding acid to keep the pH steady. It's a process and it's going to take time. You can search and read other bicarbonate startup threads and you'll see that all of them used lots of acid and baking soda.

Do the best you can with the FC. One issue with a adding bleach is that it has excess lye in it from the manufacturing process (pH of bleach is ~ 12.5) so you are adding alkalinity from the bleach which is leading to greater acid demand. But you need to keep FC in the water as you don't want a full on algae bloom.


Sent from my iPhone using Tapatalk
 
Tested this morning at 7:00am. Interestingly, FC was at 5.5 (and it was 6.5 last night at 11:00pm), so I only lost 1 ppm overnight. PH tested at over 8.2 this morning again, but I think the shade of pink is getting closer to the 8.2 shade on the indicator. I'll test again later today and probably add some bleach around midday.

I know CYA can take up to a week to read on a test - I assume it can also take that long to become effective?
 
lvrpl said:
Tested this morning at 7:00am. Interestingly, FC was at 5.5 (and it was 6.5 last night at 11:00pm), so I only lost 1 ppm overnight. PH tested at over 8.2 this morning again, but I think the shade of pink is getting closer to the 8.2 shade on the indicator. I'll test again later today and probably add some bleach around midday.

I know CYA can take up to a week to read on a test - I assume it can also take that long to become effective?
Click to expand...

OK, good. Please keep adding FC to keep your water at or above 5ppm.

That last statement is technically not true and is not based on any science I know. Once it fully dissolves, it will register on a test. The urban-legend about taking a week comes from the fact that CYA dissolves very slowly and often breaks down into smaller particulates before becoming fully dissolved. Also, people would often add CYA directly to their skimmers where it would get sucked into the filter. Once trapped in the filter, the CYA dissolves and disperses very slowly because of the much larger surface area over which it gets distributed. This is why TFP recommends the sock method in front of the pool return as opposed to the skimmer. Once the CYA dissolves in the bulk pool water, it is measurable. Many people have reported that once their sock was empty, they could easily measure their CYA. So I would say give it a try and see where you're at. If you get 0 or some low number, then you can always wait a little longer.

Keep hitting the water with acid, it will start to drop. Once you get your pH set, then measure your TA so you can figure out how much baking soda to add to bump the alkalinity up.

And, as always, brush your teeth...um, pool, twice a day :D
 
Alright, got home from work today and tested. PH is at 7.8. Is that good, or should I push it down to 7.5?

The FC tested at 3.0...even with having my wife add some bleach around mid-day. That means I probably burned up 6 or 7 ppm during the day today. I'll test the CYA levels tomorrow - hopefully that's getting absorbed into the water to help with the sunlight burn. I'll also do the FC overnight tonight again and see how much we lose - I'm skeptical that I'll get a repeat of a 1.0 drop like last night.
 

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