Urgent Tank Overflow and Parameter Swing

I had to run home from work to find out what has happened to my tank. Wife said it was overflowing and she couldnt figure out why. Long story short.....after a looking myself for a while I found a large chunk of CHEATO clogging my overflows. This of course made the ATO dump into the sump adding I would guess in the area of 8-10 gallons of pure RODI Kalkwasser loaded water. "F%$K!!!!!!" My params at this moment.
PH is off the charts. 8.8 is as high as I can register. How bad is this?
Alk 11. I hang at 9.5-10 at all times. How bad is this swing??
Salinity went from 1.023-1.0215 How bad is this?

What I am doing....
I have fixed the clog in the overflows.
I am conducting a water change but I do not have much time as I have to return to work. I have about 6 gallons of RODI water on hand (My RODI unit is running though) I have taken this 6 gallons of water and proceeded to mix it. I have attempted to reach a salinity of around 1.030.

My question.....should I attempt to bring the salinity back up quickly in this fashion by dumping highly concentrated saltwater back into the tank or should I proceed to bring it up slowly over the next few days? I am guessing I caught the system failure within 4 hours of starting. NEED SOME ADVICE. I did turn on my lights. Suprisingly all of my corals look good. All of my SPS (Acros, Birdsnest, Cyphastrea, Montis) have their polyps extended fully. My Gorgonian looks pissed but most all of my LPS corals look fine. HOW SHOULD I PROCEED???? THANK YOU!

 

Come on I know there has got to be somebody on here with a similar experience. I dont want to make this bad situation worse!

 

Should I leave the lights on or turn them off? Anybody got any ideas what the best way to preserve my system is at this point. My biggest fear is losing my SPS colonies. Everything else in the tank looks okay but some of my SPS have been giving me fits as of lately. FML

 

The Alk and salinity don't seem too bad. Make changes slowly. Raise the salinity to at least 1.024 or 1.025 over 3 or 4 days. Turn the lights off and the Ph should drop some.

EDIT: Did you check calcium? See any white residue in your tank? A large dump of kalk usually results in a precip event.

 

The ALK swing actually has me worried the most. Correct me if I am wrong but Acros are expecially susceptible to ALK swings..?

What about the massive PH swing?

No I have not checked calcium but will now. What should I expect from an event like that?????

 

i had this happen i just raised the salt back to where it was right away. i didn't have kalk in my water though at the time so i didn't have that to deal with. had low salt and a mess on the floor since the ato was full. murfys law!
i now have an apex that turns the power off to my ato/kalk water if the ph gets above 8.35 a safety for the ato/kalk

 

And before you ask yes the water has a slightly milky white appearance.

 

Yes my sump is setup as you described above. Gravity driven, the ato can only add when the sump is low. But when algae clogs the overflows the sump goes empty and bam! What should I expect from a precip event??

 

When the ph gets high it causes calcium, magnesium, and carbonate to precipitate out and form a white residue and cloudy water. Now this is all just my opinion so don't take as gospel.

The damage has been done. If you make changes too quickly you will only make it worse. You stated the alk is usually 9.5-10 so 11 is not too bad of a swing. Not good but not deadly IMO. The salinity is worse, again just IMO. If it were me, I would do a water change right away and try to bring the SG up some then another change every day for 3 or 4 days to get it to 1.025. The ph should gradually drop with the lights out and the water changes.

I've done the same thing. Everything was fine except some acros lost color and took awhile to regain it. If your acros were struggling already, you may lose some but not much you can do about it. Sorry this has happened.

 

I have done a 5 gallon water change and brought he salinity up to about 1.022. Originally I was at 1.023. So I am close but I didnt want to bring it up too fast. All lights have been shut off with the exception of 1 PC light in my sump (Should I shut it off too?) The PH is still very high. I am crossing my fingers.

I am having issues with one colony of Acro. It hasnt been cooperating. So I may loose him for sure now. Everything else looks okay though. Luckily I believe my ato source was low. So I didnt get the full 25 gallon dump. I think I got about a 8 gallon dump. Still not good. I will take any and all advice. Thanks all and I will check in when i return from work.