White Flakes Floatin'!

[YippeeSkippy]

I'm new to all this. I've been tweaking my T/A down with acid & aeration. Also since my FC was strangely high, I turned off my SWG for about a week. During this time my water has looked fine.
This morning I took it into my head to turn the SWG on again at 10% (previously it was 30%, then 20%, then off) when my FC reading was 6.5. Six hours of running and I'm seeing these large white "paint chip" looking flakes deposited under the return eyes. Easily vac'd up, thankfully. WTH? My chlorine also went up to 7.5. I've again turned the SWG off.
Latest readings tonight via my TF-100 test kit are:
FC-7.5
CC-0
pH-7.4 (ish)
T/A 150 (yay! It was 300 on 4/2, so acid and aeration are working steadily)
CH-310
CYA-75
Temp-68 (cool day, lots of aeration dropping temp)
Salt-3200

Are SWG meant to be turned off and on so? I thought they were intended to be left alone? What is winter mode and is that something I might want to use to keep it on yet low output while chlorine high?
What are those flakes, salt precipate? Residue after the SWG does its thing? I've never read anyone else here mention them so am getting concerned.

Yippy Not Skipping

 

[jblizzle]

I wonder if having your pH lower to reduce your TA actually released some scaling buildup in your SWG cell that broke loose and came out the returns.

Actually the SWG turns itself on and off all the time ... the setting is really like a percentage of time that the cell is actually generating.

 

[JamesW]

It's most likely calcium carbonate scale that has formed on the salt cell blades and subsequently flaked off as the cell went into reverse mode. You can check and clean the cell as needed. Keep the pH between 7.2 and 7.5 until the TA gets to 80 and then keep the pH at 7.8. Once the water gets over 75 degrees, keep the TA at 70 ppm.

Adding borates to 50 ppm would help prevent calcium scaling in the cell.