Bad day in the reef

Luckily I took the day off of work today with hopes of getting the boat out. Because of the weather it turned out to be a bad desicion, but I was extremely fortunate i was home. When my lights in the tank came on I walked by to take a look. Coral all looked good and open but I noticed my yellow tang laying on its side in the front of the tank, fins totally extended and stiff as a board. Upon further inspection my mandarin was laying on the sand completely stiff and breathing frantically, 2 bangaiis same thing, the clowns were twitching, the copperband butterly was laying stiff, and my powdered brown was obviously dead.

WTF

I opened my stand and noticed the new knopp c calcium reactor was running dry. Obviously this is not good.

I threw an air stone in the tank and tried to keep calm. Tested ammonia and PH. ammonia was 0 but the ph was EXTrEMLY low. I put all the pumps close the surface and rigged my koralia to the air pump to make like it act like a Venturi. After about an hour the clowns started acting relatively normal. Everything else laid where I found them, frozen. ( I wish I took pictures)

After 2 hours the yellow tang twitched, then rose from the dead followed by the bangaiis, mandarin, and copperband butterfly. ( at this point I was wishing I did not remove the powdered brown, but he wasn't even breathing.)

Ph is up to the low 8s now and I did a 20 gallon water change. The baby mandarin that I just added even made an appearance.

The only fish that are still laying still (but breathing) are the gramma, six line wrasse , the flame angel, which may be dead, and the blood shrimp (can't find it.)

So far 2 casualties (purple firefish, and powdered brown)

Has this ever happened to anybody before? What would cause a calcium reactor to empty all its contents over night. The bubble rate was slow when I looked this morning. If I'm going to re hook up the calcium reactor, I'll need to convince her it was human error, not a side effect of running the reactor.

 

I was not using a feed pump, I had a tube siphoning from the sump, and dripping back in.
Are feed pumps pretty much required with calcium reactors, if so what kind would you recommend.

The advantage of narrating my own story is I can make myself sound as calm as i like. My wife's version may be slightly different.

The Grammas fins are moving now, so I'm thinking shell make it, but the flame angel hasn't budged. He's also deep in a cave at the bottom of my rock structure, figures.

If i had gone to work this morning, I'm sure i would have lost everything. Honestly the yellow tang coming back was miraculous 10 minutes before i had picked it up with tongs to remove it, it was stiff as a board, literally like a dinner plate. lucky I had dropped it and decided to go check my water supply in the basement. 10 minutes later, it came back to life. It really does make me feel bad about the Powdered Brown though, maybe it was comatose too, unfortunately for him, I didn't drop him during removal. Oh well.

 

I've had the reactor running for about 3 weeks
There is an eheim recirculatin pump plumbed into a closed loop for circulation within the reactor. There is a siphon line on the bottom of the reactor which I placed into my sump. There is an effluent line that exits though the top of the reactor with a valve on the end to control the drip. I was using about 10 bubbles of co2 per minute, and the effluent trickled out of the end back to the sump. In my efforts to stop the damage i didn't go through what could have went wrong forensically, but my suspicion is that the shon line came out of the water and started sucking air, or draining. I'm not a physics prof, or plumber but i did have concerns about how the siphon was maintained with the effluent comming out the top. It worked for a few weeks at least. I assume the recirculatin pump had something to do with it.
I'm thinking of adding a dosing pump to the inlet to prevent a free drip in the future, I should probably invest in a ph probe for the apex jr as well.
Now my alk is measuring about 15. There were 3 total casualties I'm calling the flame angel dead at this point. Everyone else is swimming around and acting relatively normal now. I still have not seen the blood shrimp.
Is high alk bad? Can I just let it come down on its own, or should I do a massive water change? I have to believe that there was a massacre of the micro fauna that called the tank home.
For now everything that survived looks pretty good, can't say if they have brain damage or not though. This could have been much much worse.
Here is a pic


HD