Flakes in Returns but CH low . . . Help

[Bird Dog]

Hi TFP Members -

I've been using the TFP for the past 4 years with great results, however, I managed to get the salt too high and now I get "flakes" in my deep water returns. I read enough to understand that I need to drain and refill 1/3 of the pool to deal with this and I have a simple Q:

How do I drain 1/3 of the pool water? Is there a setting on my Pentair main pump that will do this or should I drop a sump pump on a shallow end step instead? Also, once drained, should I simply let the auto refill bring the pool back to operating volume or should I buy a tank truck of pool H20?

Thanks in advance!

 

[mknauss]

Those flakes are most likely calcium not salt.

What is the salinity of the water? Other test results?

 

[jblizzle]

I agree with Marty, very doubtful the flakes are salt. More likely your CH is high and/or your pH and TA are too high.

 

[ajw22]

How did you measure that your salt is too high? The only reliable salt test is K-1766 Taylor Salt Test

 

[Texas Splash]

To test .... see if you can capture some of those flakes and put them in a small pile. Drip some muriatic acid on it. If it fizzes ... calcium

 

[Bird Dog]

Got it, thanks. This year's TFP Test Kit arrives today. I'll test when I'm home from work and post full test results shortly.

 

[Bird Dog]

To test .... see if you can capture some of those flakes and put them in a small pile. Drip some muriatic acid on it. If it fizzes ... calcium

Will do and will post results, TY!

 

[Texas Splash]

This year's TFP Test Kit arrives today.

 

[Bird Dog]

Look - an answer box showed up in the mail! Time to put on my Hawaiian shorts and lab coat - let's get to work!

 

[Bird Dog]

The first picture is what the "flakes" look like at the deep water return. I used the pool skimmer net and fished a few out and placed them atop the hose reel box in picture 2. As instructed, I hit these flakes on the top of the hose box with a bit of acid and planned on taking a short video of the results but before I could get my phone out the acid had consumed all the flakes in a violent acidic holocaust!

Fantastic I said to myself! Acid will do the trick! So I emptied 4 gallons of Muriatic Acid into the pool and the problem is over! KIDDING - Relax. Onto the next post.

 

[Bird Dog]

Test Results - 05/16/2019

FC 08
CC 00
TC 08

CH 10X25=250

TA 14X10=140

CYA 25~30

Salt 1830 = 5.2 reading on test strip

 

[Bird Dog]

I think I see my problem and am more confused than ever.

HOW CAN CH BE LOW AT 250 AND THERE ARE CALCIUM FLAKES IN THE RETURNS?!?

Thanks in advance. LOVE TFP!

 

[ajw22]

What is your pH?

Is your SWG installed and generating?

 

[Bird Dog]

pH was right on target last I checked the prior weekend. I'll run it tonight once I'm home from work but my strong guess is it's unchanged from last week. No one has been in the pool. I added zero muriatic acid since I checked last weekend.

Yes, the SWG is installed and generating. FC/TC is high as the pool was just commissioned, I realize I need to step it back a bit and bring FC/TC closer to 4. But, that won't fix the flakes. How do I raise CH and get rid of the flakes? That is the Q.

 

[mknauss]

By managing your CSI (Calcium Saturation Index (CSI) - Trouble Free Pool) at between -0.3 and 0 the calcium carbonate flakes from the SWCG will be minimized. You will still get some. pH and TA are factors to manage as your CH is normally a given or less able to be controlled. Put your test data into PoolMath and it will calculate and track CSI.

 

[ajw22]

Your flakes are likely coming from your SWG. They are accumulating on the cell because your CSI is probably positive. The flakes get knocked off when your SWG changes polarity. That is the cell automatic cleaning.

I can’t say for sure because you will not provide a pH number. Being on target does not tell us anything.

Please correct your signature about your SWG and put the size cell there.

 

[Bird Dog]

I will measure pH and report this evening. THe SWG generating the flakes makes perfect sense. The SWG required acid wash/descaling multiple times last year. CSI is an issue for sure.

 

[mknauss]

With proper management of CSI your SWCG should never need to be acid washed. Each time you acid wash it you remove a not insignificant amount of life from the plates in the cell.

I manage our pool water up to 1000 ppm CH and have never acid washed the SWCG.

 

[Bird Dog]

Testing pH - is there another test you require other than the daily test to establish a plan for CSI? Did it come with the TFP Test Kit I ordered and I missed it?

 

[jblizzle]

Not sure I follow. There is no test for CSI. It is a calculation done in PoolMath based on all the other test results and water temperature.