New Tank, dead damsel...

[TonyShepherd]

Ok so to preface this - I understand many recommend and argue against cycling a new tank with fish, however, I decided to introduce a yellow tail damsel. It died overnight, and I can't quite figure out why. It ate just fine last night (mysis shrimp), however, it hid in a little cave under some of the rock from the time I put him in till his belly touched the top sometime before I woke up.

The tank has been set up for 2 days, I have 8lbs of live rock and 10lbs "live sand" from my lfs. Water params are as follows: Ammonia and Nitrite are 0, Nitrate 5ppm, 78 degrees, sg 1.022, pH right about 7.9 (which I recognize is a tad low). It's a standard 5 gallon tank with the pump from the tetra whisper being used as a power head (I suction cupped it to the side of the tank about a third of the way down the tank). I did run the filter with a cartridge and carbon for about two hours yesterday, several hours before the fish was introduced.

The aquarium was previously set up as a freshwater tank if that's relevant.

Any idea why the thing died? I'm kind of confused.

 

[bang guy]

Since it didn't die from ammonia I would suggest perhaps PH shock and/or temperature shock, and/or salinity shock. Those are about the only three things that would kill overnight.

It's not that your water parameters are bad (they seem fine as measured) but the difference between the store water and your water can kill if they are sufficiently different. What acclimation method did you use?

 

[TonyShepherd]

Since it didn't die from ammonia I would suggest perhaps PH shock and/or temperature shock, and/or salinity shock. Those are about the only three things that would kill overnight.

It's not that your water parameters are bad (they seem fine as measured) but the difference between the store water and your water can kill if they are sufficiently different. What acclimation method did you use?

Thank you for your response!

I floated the bag for around 30 minutes, then opened it, then about every 5 minutes introduced about half a cup of water into the bag until it was mostly full, then slowly tipped the bag over and slid it out of the tank.