Encrusting white layer on my rock

[needlehandssoftfingers]

This stuff showed up almost instantly, 7 week old tank and last few days I've been adding PurpleUp to help the corraline grow. I cant get a good pic but its a layer ontop of my rock and its VERY WHITE. I read it may be bleaching but this is new growth. I have very little flow in the areas covered in this. Is it possibly where stuff is settling because I'm maybe overdoing the P.U? I am getting an up to date parameter test and will post numbers below

 

[blaxsun]

I honestly can't tell from the image, sorry.

 

[Reab]

Purple up is typically a kH solution. It is quite possible this is a precipitate of the carbonates. Check you magnesium level

 

[needlehandssoftfingers]

Purple up is typically a kH solution. It is quite possible this is a precipitate of the carbonates. Check you magnesium level

I feel like I'm testing wrong (salifert) because it's been at 1200 for weeks

 

[Reab]

Have you added any? That’s pretty low and would explain why you’re getting the precipitate. I would hold off on adding anything until you get the mg up. What salt are you using and if you are dosing Mg what brand?
If you’re following the instructions you shouldn’t be testing wrong but it doesn’t hurt to find a video explanation on YouTube to verify your procedure.

 

[needlehandssoftfingers]

Have you added any? That’s pretty low and would explain why you’re getting the precipitate. I would hold off on adding anything until you get the mg up. What salt are you using and if you are dosing Mg what brand?
If you’re following the instructions you shouldn’t be testing wrong but it doesn’t hurt to find a video explanation on YouTube to verify your procedure.

Well my worry about testing is that the video I watched said to redraw until .85 and the booklet says ignore the air gap and it usually comes up at .80
The only thing I was dosing is the purple up
I've been using Fritz reef pro mix for the saltwater