Arctic Display tank HELP

[lilchris]

Last night I had a little issue w/ my tank. I came home from work and I started checking my tank, making sure everything was in order. I recently set up an automated ALk dosing pump. I wanted to check to see if everything was still working since I haven't be home to monitor it when it doses the Alk part of the 2 part. After I hit the timer button to turn it on my wife gave me a honey do list. I forgot all about it and about half and hour to fourty five minutes later I went back into the living to find a completely foggy tank. It was so bad, I could see the rocks that was right in front by the glass. I immediately remembered I turned the dosing pump on and I shut it off. Not sure how much go dripped. I check my PH monitor and it went from 8.1ppms to 8.4ppms by the time I caught it. I did a 19 gallon water change last night and I have another 15 gallons that I am going to do when I finish this post.
I check the live stock this morning when everything kind of settled they are all doing good, (so far no sign of stress.) It looks like an Arctic display tank. All the rocks are white the sand bed is clean and covered white.
My params are as follows:
Everything w/ Salifert test kits
KH 19.5 very high
ALK 6.9 ditto

CA 270 very low
MG 1170 ditto'

Salinity 1.025
PH 8.4 last night at the discovery of this disaster about an hour later it dropped to 7.9 wierd right now it is 7.9 no lights on.

TEMP. 79.9

What happened??? I don't think it was a gallon that was dosed. I do use Kalk w/ my top off. I think it was a chemical reaction. What should I do to get this stuff out of my tank. It looks like there was a lot of precipition(sp). All my corals are open (softies, polyps, and LPS). I do run carbon. I am going to do another water change. How many should I do. I am using Randy's 2 part recipe 1 I think. W/ the baked baking soda. Also I am currently doing a 50/50 mix of IO and Oceanic.

[lilchris]

Sorry for the type o's in the first post. To make a long story short. I have a completely foggy tank. It has since cleared up due to the water changes, it think, also from everything settling down. I have completed a 20 gallon water change last night, and a 15 gallon water change today. I will do another one tonight or tomorrow. I hope I can get some guidance on this, I know it is Christmas eve and people have more important things to instead of surfing REEFCENTRAL.
Merry CHristmas

Please refer back to my first post for the tank params.

[capn_hylinur]

with the mag level you have I would think that it was too low to hold that level of alk and what you are seeing is precipitation of carbonates.
I would use Kent Tech-M and bring up the mag level. There is a calculator on the first thread in this forum. (1300 ppm)

The alk will fall down on its own probably over the next 3-5 days to a level where there is no more precipitation or it will settle out enough that you can start to lightly baste the rocks etc with turkey baster-----good timing--xmas dinner will be over by then-LOL

[oct2274]

get the mag level up to atleast 1300 and it will help the precipitated calcium issue

[bertoni]

I agree that the cloud was likely calcium carbonate, due to overdosing alkalinity. I'd get the calcium and alkalinity back to normal with a couple of doses. Getting magnesium up would help as well.

The precipitate will disappear on its own.