Did high calcium kill my crustaceans?

[AlexKintner]

This is a stupid thing I did a while back, and has been bugging me ever since...

I accidentally mixed a half-strength batch of alkalinity... along with a full-strength batch of calcium. For the next 4-6 weeks I proceeded to add both components in a 1:1 ratio. To complete the fail... I only tested alkalinity.

First sign of trouble I noticed was a pistol shrimp and a couple ornamental crabs dying in quick succession. I then tested all parameters (including calc) and realized what I had done. I couldn't even get a calcium reading (using Salifert) but I estimate it was close to 800 ppm.

While slowly returning calc levels to a normal range over the next couple weeks, I noticed that my previously thriving pod population had completely crashed. It seemed as if everything in my tank that molts had died. Predictably, things went south after that as I battled every nuisance algae and bacteria imaginable.

All is beginning to look better now as I have reestablished the micro-fauna population, but I post this today for a couple reasons:

• A reminder - Please be careful mixing your 2-part (and test both parts)
• A question - Is it possible that high calcium killed ALL of my crustaceans?

Thanks in advance

 

[Lavey29]

High calcium won't hurt inverts but high magnesium will.