New QT offed fish within hours

[k1ngofthrones]

Hello again! I started setting up a QT, bare bottom with nothing in it, with activated charcoal as filter media. I used some API instant cycle live bacteria, let it run for several hours, and chucked in a yellow tail damsel. He’s extremely aggressive and very rude for his small size so I figured I’d use him to test the bacteria since I was advised to get rid of him anyways. He was perfectly fine in the acclimation bucket as well. Went to sleep, woke up about four hours later, and he was lying dead on the bottom of my QT. He did not lose any of his coloration like he does when he sleeps either, so it was like he just dropped dead. What could have killed him so quickly? He did not have velvet or any other issues like what was in my DT. FYI, I am NEVER this careless with my other fish!! Just wanted to test the bacteria, but I have never read anything about them dying that quickly in an uncycled tank, he did not have any sort of redness in his gills or anything like from ammonia burns. The salinity matched my DT tank pretty closely and I acclimated him just in case my hydrometer was off a bit.

 

[W1ngz]

I'll spare the lecture about testing with test kits, and not live animals...
I can't find anything called API instant cycle on google.
Do you know at all what your ammonia, nitrite and nitrate levels are in that tank? Ammonia is quickly lethal after a point.

 

[Ox100]

sounds like you killed him that tank was not cycled and didn't have enough bacteria. sorry

 

[Cell]

I doubt the ammonia could be built up to a lethal level with just 1 damsel after 4 hrs.

 

[AZMSGT]

What kind of water did you use? Tap water? What kind of salt did you use? Go back to basics and lets see where it went wrong.

Guessing it was API quick start that you used not what you said. Not familiar with this product but I tend to be cautions with this instant start up products. Bio Spira I have used in an emergency to get a QT up and running and it worked.

Also the charcoal might have pulled all the bacteria out and left your fish with nothing. Also what was providing oxygen to the system? Did you have a bubble stone?

 

[k1ngofthrones]

Yes, I had one of those bubble stones in there. I didn’t monitor the ammonia very closely because I didn’t think there would be any, but never leave any stone unturned I suppose. Everything else was within acceptable parameters otherwise. Suffice to say that despite the sources claiming you can cycle with damsels/clowns I will not be trying that or “instant cycle” stuff again. I might try to use activated charcoal as filter media again in an already established tank though, I’ve read it can be very beneficial. Thank you for the advice everyone!

 

[W1ngz]

Using activated carbon in a filter is beneficial, but it shouldn't be the only thing in there. It also should never be used when dosing medications.

There should be some sort of filter pad for dirt and detritus as well as a foam or ceramic biomedia for bacteria to grow on.