Calcium precipitation

[Yanos]

Hi guys. calcium problems.
Don’t know why, but for some reason, without the reason, I’ve noticed that Water got slightly milky and my rock work is being covered in white sort of powdery film. Initially I thought I’m bleaching my rocks with too much light, but corals themselves are happy, so I dropped this idea.
Yesterday I’ve noticed that my glass magnet is covered in same white powdery film. So I came to conclusion, calcium precipitation.
now, how on earth this have happened and how do I get this sorted.
I’ve just over 270 gallon DT.
Calcium, Magnesium and Alkalinity are dosed from my calcium reactor.
Parameters been very stable for last few months, finally lol and read as follow

Temp 26C day time 25C night time
Ph 8.24 day time, 8.13 night time
Kh 8.6
Ca 430
Mg 1320
No3 0.2
Po4 0.012

What am I missing on?
Cheers

 

[Randy Holmes-Farley Verified Community Expert]

Maybe the reactor had a flow surge and dumped out some fine powder?

Maybe it's fine sand that was stirred up?

massive precipitation events happen at high pH and high alk, neither of which you have, although such events will bring both back down from a spike.

This has more:

What is that Precipitate in My Reef Aquarium? by Randy Holmes-Farley - Reefkeeping.com

http://reefkeeping.com/issues/2005-07/rhf/index.htm