Rambo Pajama Cardinal

[Dougan2469]

I have a new 150 set up and used a pair of small pajama cardinals to cycle the tank. They where in the tank for around 2 weeks and everything was fine. Yesterday at lunch I came home to check on things and found both fish in an epic battle for life or death.

This morning the smaller of the two was dead and 1/2 eaten by my cleanup crew. The larger is fine...

All my parameters are fine and since the cleanup crew was doing such a good job on it I left the other 1/2 fish in the tank "dinners served boys "

Any ideas as to why this would be? I did not think cardinals to be that aggressive of species.Especially to there own kind. Must be those red eyes...

 

[Bernie21]

All my parameters are fine

Define "fine"...

 

[snorvich]

You used live fish to cycle a tank? If your LFS advised that I would change LFS. They most likely had their gills damaged from ammonia.

 

[Dougan2469]

Ok... let me rephrase this...

The tank had been up for a few months with 130 pounds of dry base rock and 20 or so pounds of live rock from my smaller tank. Have had reef tanks for many years and used this method many time in the past with 100% success.

The pajama cardinals where a first I added to my new tank before I added anything from my smaller aquarium. The bio load from 2 fish a little larger than a 1/2 dollar in a 150 gallon tank with a 75 gallon sump would be VERY small. Besides I liked them and they where on a killer sale at our LFS.

I have had all my parameters spike and all my tests where back to "0" Went with the stinky shrimp method to actually cycle the tank.

Define fine? Swims around looking happy as can be. Eats everything I throw at him. Aside from taking him out and teaching him to talk. My analysis is "fine"

Now... back to my original question, Anyone else ever have a problem with pajama cardinals becoming aggressive to its own species?

 

[prettyfishy76]

Ok... let me rephrase this...

Now... back to my original question, Anyone else ever have a problem with pajama cardinals becoming aggressive to its own species?

Yes. I started out with a group of 5 and ended up with 1 fairly quickly. He beat everyone to death. I've had the single PJ cardinal for 5 years. I don't even bother thinking he'd want any friends because I know he definitely does not.

Now, orbiculate cardinals (they look like a black and white version of the PJs), even though they are rather boring in appearance, do really well in groups. I kept a group of 10 for 2 years before I gave them away. They were always huddled together.

 

[Betta132]

Threadfin cardinals are also good.

 

[Bernie21]

When I said define fine, I was referring to your parameters, not your fish.

 

[tidus10]

All my parameters are fine and since the cleanup crew was doing such a good job on it I left the other 1/2 fish in the tank "dinners served boys "

Define "fine"...

When I said define fine, I was referring to your parameters, not your fish.

You cannot judge water parameters by the look of the fish, we are requesting actual numbers like
Salinity: 1.025
Temp 79.0 - 81.0
PH: 12.7
ect
ect

Not asking "how do your fish look? Are they swimming well?" because if that were the case they wouldn't be dead...

 

[Bernie21]

Lol at PH: 12.7

 

[Betta132]

That's definitely something to check. I mean, HOW could a cardinalfish kill another cardinalfish? They don't have spines or poky bits, and their mouths (though large) have no teeth or anything like that. I'm not sure how a cardinal is physically capable of killing something that fast... maybe harass it to death, yes, but that would take more than a day.

 

[lhm nole]

That's definitely something to check. I mean, HOW could a cardinalfish kill another cardinalfish? They don't have spines or poky bits, and their mouths (though large) have no teeth or anything like that. I'm not sure how a cardinal is physically capable of killing something that fast... maybe harass it to death, yes, but that would take more than a day.

You would be surprised how a bangai cardinal can demolish another of the same sex in a few hours

 

[Betta132]

But how do they manage it, physically? Do they just slam into it over and over?

 

[Jshafer]

+1 on the bangii cardinals male vs male.. In my experience one will be killed within 12 hrs

 

[Dougan2469]

I am posting at work and don't have the numbers in front of me but none of my tests showed elevated or low numbers.

"How did one fish manage to kill the other?"

Smashing in to one another at speeds I did not think capable from such a small fish.
They would have a stand off for a few seconds from across the tank then "WHAM" back on one another.