Mystery White Stuff

[JupiterFL]

Any idea what this white stuff could be? Found it near a return bubbler on sun shelf.

It dissolves if you rub it between your fingers.

I was thinking maybe calcium, but my water chemistry seems to be in reccomended ranges.

Using a PH meter for PH.

 

[Rancho Cost-a-Lotta]

Calcium flakes generated by your SWG. When it reverses polarity, scale is sluffed off the plates. Your numbers look good, but lowering TA should eliminate most of the scaling. It's been awhile since you tested TA. You might want to retest.

 

[JupiterFL]

Thanks!

 

[Rancho Cost-a-Lotta]

For what it's worth, your numbers are almost identical to mine, along with the pool temp. If I allow my TA to rise above 80, I'll start to see the scale. For whatever reason that's my magic number. I recently went through a somewhat aggressive process of lowering TA down to 70 which completely eliminated scale from the cell.

 

[BDY]

Pour some vinegar or MA on it. If it fizzles it’s calcium and you should check your CSI for SWG management (and check the cell too for any scale)

 

[JupiterFL]

For what it's worth, your numbers are almost identical to mine, along with the pool temp. If I allow my TA to rise above 80, I'll start to see the scale. For whatever reason that's my magic number. I recently went through a somewhat aggressive process of lowering TA down to 70 which completely eliminated scale from the cell.

I haven't added any fill water since I last tested TA (I have added MA). Is there any other way TA would rise besides fill water (aside from intentionally adding something)?

 

[Rancho Cost-a-Lotta]

Something would need to be added to the pool to increase total alkalinity.

If your total alkalinity hasn't changed, perhaps your water temperature has increased. This would also contribute to scaling in the cell. The environment in your cell while it's producing chlorine is much different than the rest of your pool water. Here's an excerpt from TFP Wiki:

Why Should TA be Lowered with a SWG?
Usually a TA on the high end is fine if the pH is stable. However TA does need to be adjusted down with an SWG. The problem is, INSIDE the cell, the CSI is very different than in bulk pool water.[3]

With high TA and aeration from the bubbles the SWG creates, you'll get faster pH rise inside the cell and so there's more potential for scaling. With current reversal, the cell tends to stay clean but you'll get more snowflakes out of the returns. Calcium hardness is only one part of the equation.

 

[JupiterFL]

Thank you