Help! Can't shake the flakes

[PsyPool]

Hi There.

I'm a new pool owner. I've been lurking the forum for the last 6 months since we built our first pool back in November. We've been doing all the maintenance so far. Every week we take a sample to a store and they recommend what chemicals to add. Anyway we have these flakes that come out of the jets for the past month and they seem to have gotten worse. I've read a bit about what they can be (calcium scale flakes?) and I've tried to clean out the salt system with a 1:4 acid/water but to no avail. I have the latest print out from the store and I think these are the right acronyms...

6/9/2016

FC 3.0
CC 3.0
SL 2400
CH 200
CYA 10.0
pH 7.8
AD 2.0
TA 100.
edit:
Temp: 87F
CSI from PoolMath 0.09

We've been regularly adding acid (edit: sulfuric, not muriatic) like every week but we can't seem to get the pH down to 7.4. Our salt system tells us the salt level is at 3200 so I'm not sure if that number above is entirely accurate.

Here's a picture of some flakes: pool flakes - Imgur

I'm pretty resourceful and try to figure things out on my own, but I can't seem to shake the flakes... Any advice you guys could provide me would be awesome!

 

[pooldv]

Welcome to TFP!

Do they fizz up if you pour a little acid on them? If yes, then it is calcium scale. To prevent calcium scale enter your test results in Poolmath, link above. It will calculate a CSI score, keep this number between -0.3 to 0. Tweak PH and TA to adjust CSI.
More here, Pool School - Calcium Scaling

Here is what we are looking for on test results
FC - Free Chlorine
CC - Combined Chlorine
pH
TA - Total Alkalinity
CH - Calcium Hardness
CYA - Cyanuric Acid (stabilizer)
Borates - (if you are using borates)

TFP is based on having a good test kit and testing your own water.
Read Pool School here, ABCs of Pool Water Chemistry
And here, Pool School - Getting Started
See if you are interested in learning how to maintain your pool TFPC style.

 

[PsyPool]

Hi pooldv. I've edited my post. The CSI from the pool math thing says it's at 0.09. The flakes do fizz with (sulfuric) acid.

I don't have my own test kit yet, but there's a pool store about 5 minutes from my house that gives me a printout for free so i've been using that. I can pick up the recommended test kits if necessary. For the time being, those numbers that the water analysis report should be relatively the same as if I used a test kit right?

 

[pooldv]

No, pool store test results are often not accurate. Pool stores are bad at testing for a number of reasons. Poorly trained kids, bad lighting, imprecise testing techniques, not rinsing out the last customer's water thoroughly.

Here is a comparison of the recommended test kits, Pool School - Test Kits Compared. I use the TF-100 from TFTestkits.net

That CSI is not good. We can make adjustments to correct it, but it would be better to do that with your own test results from a good test kit. We've had lots of people make their pools worse by relying on pool store test results.

 

[PsyPool]

Thanks. I'll order my own kit... TF-100 seems good. Do I need the salt test, or should the reading on my automation work fine?

In the meantime, what could be the cause of the flakes? I'm reading that I should probably switch to muriatic acid instead of sulfuric acid and get the pH down to 7.4.

 

[pooldv]

Generally, using the salt reading on the SWG is fine. I test salt once or twice a year just to be sure. I use the salt strips from TFTestkits.net.

The flakes are caused by calcium scaling. Reread post #2 above, I covered it there.

 

[PsyPool]

Hi pooldv. Thanks for your response. I read the information about calcium scaling on the site. I don't know if that's the same issue... There's just flakes, no cloudyness, nothing on the pool surfaces. The CSI calculation based on the numbers above seems to be within acceptable limits. I don't think it will require a full drain and acid wash. I don't know if it matters, but the pool is only 6 months old.

I did order the TF-100 kit, so I can hopefully get a more accurate test soon.

Is there anything I should do in the meantime before my test kit comes?

 

[pooldv]

What you have is calcium scale, it tends to build up in the SWG first and then migrate as conditions persist. It is a long slow process. And by the time you notice it you are months or years down the road.

You definitely do not need an acid wash. Because you are very early in the process all you need to do is keep CSI between -0.3 and 0 to prevent scale going forward. Whatever you have now will dissipate and be fine.

 

[PsyPool]

Hey everyone,

Just an update. I switched to Muriatic acid from Sulfuric acid and the flakes stopped showing up for the most part. I still see some remnants floating around sometimes, but they aren't shooting out of the returns anymore. I also ordered a TF test kit and just did the full gauntlet of tests today.

FC - 3ppm
CC - .5 ppm
pH - 8
TA - 100
CH - 250 ppm
CYA - 20 ? (i filled the whole vial up)

Temp - 91F
Salt - 3000 ppm
CSI - 0.37

We are constantly battling the pH. Seems like we're adding a cup or two a day. I guess it's time for some stabilizer?

 

[jagger2005]

Definitely get your stabilizer to 60-80. I would dose to raise it from 20 to 50. This will give you some wiggle room if your pool gallons estimate is higher than actual. Use the sock method over a return when adding stabilizer. In a couple days measure the Cya again to see where it landed and dose to get to the 60-80.

You have a pretty new pool and SWG, so your pH will tend to rise. What I did was use PoolMath to dose for 7.2. Once I hit 7.8, I dosed back down to 7.2. After I was able to go about 4-5 days without adding, I started dosing for 7.5. I now only add about 12oz every 2 weeks and my TA settled in around 60-70. I started at 130.

Oh yah, welcome to TFP


Sent from my iPhone using Tapatalk

 

[tucsontico]

Hey everyone,

Just an update. I switched to Muriatic acid from Sulfuric acid and the flakes stopped showing up for the most part. I still see some remnants floating around sometimes, but they aren't shooting out of the returns anymore. I also ordered a TF test kit and just did the full gauntlet of tests today.

FC - 3ppm
CC - .5 ppm
pH - 8
TA - 100
CH - 250 ppm
CYA - 20 ? (i filled the whole vial up)

Temp - 91F
Salt - 3000 ppm
CSI - 0.37

We are constantly battling the pH. Seems like we're adding a cup or two a day. I guess it's time for some stabilizer?

I'm not an expert, but what I've learned from this website has allowed me to care for my pool easily and cheaply. The turbulent water flow through the SWG acts like aeration and raises the pH of the water (think of carbonated water). Putting 2 cups of Muriatic Acid (MA) a day is not uncommon. Every pool is different and, based on how much you run your SWG, you may need more or less. The other thing to consider is your pool is still "new" and it may take an entire year of "curing" the new plaster for the MA use to drop off. After my first year, I still had to add nearly 2 cups per day to hold the pH at 7.8. I finally installed a Pentair IntellipH system to automate this chore.

According to your test results, your Total Alkalinity (TA) is too high. For an SWG you should be between 60-80ppm. That fact alone could help you control the pH better. I would also recommend bringing your CYA up to the recommended TFP Pool School amounts (70-90 for an SWG pool). Do it slowly and aim for the low end! Also, be advised, it can take up to a week after adding CYA for the correct amount to register on the test. I highly recommend you re-read the Pool School article: Pool School - Water Balance for SWGs.

BTW, due to my pool being in the full, hot Arizona sun, I have my CYA at 70 and also added Borates to 30 ppm. My SWG runs about 5 hours per day (at 70% capacity) and I hold 2-3 ppm FC easily. A little study and POP (Pool Owner Patience) will reward you with a crystal clear Trouble Free Pool!
Good Luck!

 

[pooldv]

Good post, except note that FC at 2-3ppm is too low for CYA of 70. Always keep FC above minimum for your CYA to keep your pool properly sanitized, [FC/CYA][/FC/CYA]

 

[tucsontico]

Good post, except note that FC at 2-3ppm is too low for CYA of 70. Always keep FC above minimum for your CYA to keep your pool properly sanitized, [FC/CYA][/FC/CYA]

You, sir, are correct! It was a typo and I do keep my SWG pool at 3-4 ppm FC.