Aeration/current issues, feeding & fish death

[Mabu]

I had a fish die on me the other day and I want to confirm what I think happened.

What I have been doing sometimes is when I feed my tank, I'll shut off the protein skimmer and filter and put some food and let is circulate around a bit. Sometimes I will also turn off the three circulation pumps I have in the tank. what I have done is drop an airstone in the middle of my 55g and use that for aeration and circulation - this way food doesn't get sucked into any of the filters or pumps and I maximize what gets around.

However, the other night I did this and I left the pumps off for longer than I do usually and the next day one of my fish was dead. There were no signs of attack at all. I'm thinking I may have inadvertently suffocated the fish? Would the aeration stone not be sufficient if the fish (wrasse) were in some rock nook and stayed there? Or is there another possible cause of the death?

 

[Mouse]

Providing that sutting off your filter doesn't include some sort of trickle filter or other bio medea then you can have it off for as long as you like. Otherwise you may have destroyed some of the denitrifying bactereal colony which in turn caused a spike killing the fish, but i sereously doubt it. And as for suffocation the fish would have been gasping at the surface long before you would have killed it. Dont know dude, bad luck i guess, if you can tell us your system equipment list and water peramiters we might have a better idea.

 

[Mabu]

I have a 55g with a BakPak II and a Millennium 2000. I also have a DSB with a plenum and lots of live rock. I have 3 circulation pumps in the tank. On occasion, I've shut everything off and put an airstone in the center of the tank while I've added food for inverts - this way to keep food from being sucked into the pumps.

Is it possible that a sleeping wrasse would have suffocated? Do they need a lot of water movement? I cannot ID the cause of death.

 

[Mabu]

Two of the circulation pumps in the tank have filter elements on them, which probably harbor a lot of bacteria, but they remain submerged so I don't think that would cause a dieoff. The two external units I have, the BakPak II, and the Millennium 2000 have had any biological element removed. I use the BakPak for protein skimming, and the Millennium for chemical/physical filtration (though maybe shutting it off may kill any bacteria in the filter element, I can't see that causing a spike.)

 

[Xphixer2]

How old was the wrasse? It may have been just enough stress to cause it to die. I have had fish die after a month unexpectedly and have attributed it to the methods of collection (cyanide poisoning weaking the liver) and just the general stress of the whole process. I would tend to agree with the previous posts that it wasn't lack of oxygen or a spike from the shutdown. sometimes they just die.....

(or jump out commiting fishicide.. I have had a few do that. and it was a Flame wrasses from Hawaii. very spendy $$$)
Rich

 

[Mabu]

I've had this happen twice. It only happened when I turned off all the pumps and put an aerator in the tank. One time I did it overnight. Both times, a fish died (my false perc though seems to be completely bulletproof). Both times were with fish that were more than a month old. There was not a mark on either fish. Is it just bad luck?

 

[Mabu]

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