White flakes in water

Recently, starting about 3 weeks ago, I started noticing white tiny flakes in my pool water. When I grab some with my net, they breakup with fingernail pressure, and dissolve. What are these?

The pool clarity is very good, this is the pools 4th season. It's a SWCG pool, plaster/gunnite. Balance is:

FC=3-6ppm (typically)
CC=0
PH=7.6 (requires weekly 3 cups of Muriatic to maintain)
TA=180ppm
Calcium= 710ppm
CYA=60ppm

Note: we did clean tiles this spring, using a pool pumice type stone from Leslie pool.

Any help is greatly appreciated.

Steve,
I don't know how to advise on this problem, but somebody will come along shortly who hopefully will be able to.

I just wanted to say hi and glad to see you back around the forum this year! You have been so supportive of me in the past couple of years offering prayers for me during my illness. I really appreciate you. Say hi to Bev also!

No problem whatsoever, thanks Lisa! We're just glad to hear that life is being kind for a change.

I'm happy to report that this has been my first pool "issue" but I'm here reading quite often.

Steve

Sounds like maybe calcium precipitating out of the water. Your very high calcium level would support that. Not sure what to do about it, your TA and pH are already on the lower side--hopefully the chemists in the group will be by shortly to offer some help.

Just wanted to welcome you back to the forum!

Janet

Most likly calcium. When your salt cell reverses polarity to 'clean' itself the calcium that had formed on one set of plates is released into the water. It is usually a good indication that you are letting your pH climb too high, which will lead to precipitation of calcium carbonate givin your high calcium levels.

My suggestion would be to bump your CYA up to 80 ppm and lower your TA to about 70 ppm. You might also want to consider adding borax to 50 ppm to your water to act as a secondary pH buffer. This has been found to be extremely useful with SWGS. I would also lower your output a bit so the FC is closer to 4-5 ppm. 7 ppm is overkill and just means the cell is on more than it needs to be. This leads to a faster pH rise which causes the calcium precipitation.

Done together the above suggestions will have the effect of causing less outgassing of CO2,which means your pH will not rise as quickly, which means you will be less likely to precipitate out calcium carbonate.
Also, you will find that you will not need to add 3 cups of acid weekly.

Once you make these adjustments keep the pH at 7.6 and not lower (lower pH causes faster outgassing and faster pH rise) and when the pH climbs to 7.8 add just enough acid to lower it ot 7.6 and not lower (this is where an acid demand test is very useful.)

The why behind my suggestions has been discussed at length on a different pool forum that I am no longer associated with because of 'new management' but that I was a moderator of since it's inception up until I left shortly after the management change.

Bottom line, my suggestions are the key to a salt water pool that is basically "trouble free";).

Appreciate the assistance, I did notice (to my surprise) that my salt cell was pretty loaded with calcium (a first), as I cleaned the cell at close last fall. I cleaned it again last night. I'll up my CYA level and recheck TA.

About PH control---

Is it ok that I just check/adjust PH every Saturday, or should I be adding less acid spread over several days?

After testing the pH a few times/week, you'll soon get a feel for how fast it is rising. I think I would test it every 2-3 days for a couple weeks, then you can adjust from there after you get a feel for how often/fast it is rising.

Janet

If you take the time to follow the suggestions I made you will minimize the pH rise and have a more stable pool. Until you do test pH daily. Once you know the pool you can test less frequently. Keep a record of your test results.

to give you an example, my acid usage went from about a quart a week to about a cup every 6 weeks after dropping my TA and adding borates. I have also seen such results in my customers pools when they adjusted the water chemistry as AI suggest. However YMMV since there are several factors that can have an effect on the acid demand of a pool such as the presence or absence of water features, pool surface, bather load, etc.

However, keeping the CYA at the top of the recommended range (usually 80 to 100 ppm, depending on manufacturer), running the cell only long enough to maintain a 3-5 ppm FC level, lowering the uncorrected TA to 70 ppm (or possibly even lower--with your high calcium your water will still be 'balanced'), AND adding borates to 50 ppm will have a positive effect on your pH stability and lower your acid demand.

Here's some updated numbers (tests redone last night), I don't know where I got the first set--my apologies:

FC=typically 3-6ppm (currently 65% output on SWCG/8hrs filtering/day)
CC=0
pH=requires 3 cups of muriatic once a week to maintain 7.6
TA=180ppm
CH=710ppm
CYA=was 60ppm, more CYA added last night
Salt=2600ppm (2250-2750 recommended by Manufacturer)

I added CYA last night to bring it up to 80ppm, but have to wait a day or two for it to settle in for an accurate reading.

My pH basically holds for 3 days, then needs muriatic to correct. 2 seasons ago, I just started checking every Saturday and correcting to simplify things--I've got the "pattern" of my water down well through the last 4 seasons, and this is the first issue I've had. I've never had any CC in the pools history, nor any need to add anything other than CYA and Muriatic. I'll go back to checking pH every other day and correcting--this fall I'll do some partial drains to get my calcium level in check.

Thanks all for the information, Evan I'll likely try the borate "trick" as well.

Quote:

---

Originally Posted by steveinaz

Here's some updated numbers (tests redone last night), I don't know where I got the first set--my apologies:

FC=typically 3-6ppm (currently 65% output on SWCG/8hrs filtering/day)
CC=0
pH=requires 3 cups of muriatic once a week to maintain 7.6
TA=180ppm
CH=710ppm
CYA=was 60ppm, more CYA added last night
Salt=2600ppm (2250-2750 recommended by Manufacturer)

I added CYA last night to bring it up to 80ppm, but have to wait a day or two for it to settle in for an accurate reading.

My pH basically holds for 3 days, then needs muriatic to correct. 2 seasons ago, I just started checking every Saturday and correcting to simplify things--I've got the "pattern" of my water down well through the last 4 seasons, and this is the first issue I've had. I've never had any CC in the pools history, nor any need to add anything other than CYA and Muriatic. I'll go back to checking pH every other day and correcting--this fall I'll do some partial drains to get my calcium level in check.

Thanks all for the information, Evan I'll likely try the borate "trick" as well.

---

If you can get your TA down you will see a big improvement in lowering your acid demand. In your case, with your high CH I would shoot for around 60-70 ppm.
Do this BEFORE you add the borates or the borates are not going to give you any real advantage besides the algaestatic one.

Ok. Will do.

remember to monitor your FC since you will see a small decrease in chlorine demand when you raise the CYA and most likely a larger drop in chlorine demand when you finally add the borates.

Well, I've got a serious case of anal-cranium disease. Checked my CYA last night, it's in the 45-50ppm range. A trip to Walmart will fix that tonight. I have re-run all my tests, I guess some of my results were out of date. I usually run all tests in the spring, and then just test Chlorine/pH throughout the swim season. I'm also going to replace a bunch of my reagents this evening.

My pool is so easy to care for, but it's lulled me into a false sense of security. Let me get some numbers normalized, and go from there. Right now here are the numbers (tested, again, last night):

FC=3-5ppm typically
CC=0
pH=7.6 but requires 1/2 cup acid every other day to maintain
CH=710ppm
TA=180ppm
CYA=45-50ppm
Salt=2600ppm (2250-2750 recommended)
Water tmp @ testing=86 degrees

I'll bring the CYA up to 80ppm, and I'm beating down the TA. This fall I'll do a sizable drain to lower CH. I'm also going to replace the QuikChlor SWCG with an Aqua Rite XL. In spite of the numbers, the water has looked/felt great all summer; crystal clear (minus the white flakes), though I believe it was a calcium ridden salt cell that caused that glitch.

An update. After 2 cleanings, my salt cell looks like new, so I got that taken care of. BTW. I tried to find PVC pieces to build a cap for my cell, making cleaning easier, and less wasteful---no luck. So I found an interesting solution...at Target they had a large cylindrical glass vase. Perfect diameter and height for cleaning my salt cell---plus, being glass I can see the cell blades through it to watch the progress. Anywho...

FC=5ppm
CC=0
pH=7.5
TA=160ppm (20ppm drop from 5 days ago)
CH=710ppm (this will be addressed in the fall)
CYA= (will test on Wednesday, waiting for added CYA to dissolve fully)

I've been hammering the pool with acid, daily, and now have the CORRECT phenol red solution (R-0004). We're already noticing the clarity/quality of the water greatly improving. I'm targeting 80ppm for CYA, I'll see where we are on Wednesday.

Thanks for the update. I was wondering about you when I made a quick sweep through the forum early this morning and your name caught my eye. Glad things are improving for you.

My posts lately look like a repeat of 3yrs ago...:D

This time I'll be more patient and fix it RIGHT.

That's where the POPP--pool owner patience and persistence--kicks in!! It's too bad we have to learn it the hard way, but I think we all have to go through it at some point in time!! ;) Glad your pool problems are cleared up. And thanks for the update!!

Janet

Flakes are gone, go here for a continuation...http://www.poolforum.com/pf2/showthread.php?t=10034