Thoughts on unnexplained (and very sad) die-off

[jostafew]

SOLVED!!!

Had a good chat with the LFS eliminating a bunch of possibilites and finally we settled on the theory that I had a bad batch of salt. Timeline fits, slow decline starting in the summer time getting the worst around the end of the year. Started using that bucket (which had a noticeably different texture) in the spring of 2012 and just finished it when the new tank went up in Jan which coincided with the loss of my last few animals.

As a verification I set up the QT tank at work with new water and moved all existing live rock (and corals that had encrusted) into that tank for holding. I then completely drained the main tank, and got rid of the existing sand. Iin went brand new water, new sand (live) and a couple pieces of new rock. A couple quick adjustments to Calc and Alk and my levels were spot on target.

After allowing it to cook for a little while the corals in there were looking noticeably better. Confident that the tank was more habitable I tried a couple cleaner shrimp which have been doing great for a few weeks now. That told me that my hardware was good, no toxins leaching from the tank setup.

Next step was new sand and new water in the nano but kept the LR that was pulled from the big tank back in November. After some time to stabilize, in went some test critters, which again are doing great. So as of late 2012 the live rock was not toxic.

Last confirmation was to place a canary (peppermint shrimp) in the QT along with the live rock and see what happens. This would be the highest concentration of rock to water, so if there was something toxic leaching from the rock it would show here for sure.

I'm happy to say that the shrimp is still looking good, so the rock is safe and come home finally!

So problem confirmed, I had a bad batch of salt that spiked my Calc and Mag and who knows what else. Lesson learned; measure the first couple buckets coming from a new batch of salt before going into the tank. Pretty scarry though, I never would have thought something like this could happen. And of course when things start going badly what's the first thing to do.... water changes.... In my case just making the problem worse.

I'm not going to name the salt brand as I'd used it for a couple years before hand and I know tons of people who use it without problem, but to the knowledge of the LFS I am the 2nd person this has happened to so it does happen.

Hope this helps someone to find the cause of their problem before they lose all their beloved livestock like I did.

Happy reefing!