[CoolD]

my tank has plenty of oxygen in the water from the powerhead, so why is it sometimes a piranha will rush full speed to the top then go back down and let out huge air bubbles out of his mouth??

Why do they do that sideways scratching motion thing against the gravel?

Why do they react so violantly towards most fish and then the odd fish you put in there ( not in all cases ) they will allow to hunt with them and acually grab food from their mouths just as if it were another piranha?

why are they such shy fish?? i cant imagine them having too many predators in the wild, so how come so shy??

Just some thoughts from cool D

 

[Raptor]

Rushing to the top and grabbing air i believe is them filling their swim bladder. It helps them go up and down. Scrathing i believe is the reason. To some irritation to slime coat, Parasite, etc.
I'd be skittish swimming in the amazon.

 

[RhomZilla]

There were past threads about Ps rushing to the top of the tank for no apparent reason. One conclusion I've came up with is that the top part of the surface shows a reflection.

Sideway scratching is their way of scratching an itch. BUt be sure to watch them closely if they do it more than common. PArasites might be involved.

Ps in general are sneaky buggers. Once a new fish is introduced, they wont take it mind. Their way of making the other fish comfortable. Then they'll ambush later on.

 

[Raptor]

Ever watch a p after acclimation. All mine have done this after 5 10 min after introducing them. Thats why I think it is swim bladder related.

 

[CoolD]

maybe reflection, but maybe swim bladder too.
i guess they do need air to raise and sink.
And if they actually leave the fish alone only to ambush it later and it is all part of a plan... WOW what smart fish.
And thats true about being freaked swimming in the amazon, the things that lurk there!!!
i was reading about wolffish, in brackets beside the name on one of the fish i was looking at had " piranha killer" .
wolf fish must be pretty hard core to go into a pack of piranhas and pick them off.

 

[Piranha King]

:rasp: why ask why?

 

[bobme]

They are cool fish, i think they are shy becuase look where they are and where they came from. I also think the bottoming craching its a itch, and maybe to stop things from growing on them. But i could be worng. But dogs do it also. All things get an inch. And i dono about the rush swiming.

 

[pcrose]

well they can't always be aggresive, I think there are some birds that will try to swoop and catch one like any other fish if there isn't to big of a pack and the bird is swift enough. I could be wrong, but I know that amazon crocs find them tasty. Yeah they rush to the top to fill the swim bladder so they can obviously swim around up and down. Scratching thing every living thing gets a scratch and yeah it could be slime coat or parasites. I am trying to make sence here.

 

[o snap its eric]

as we all know, single piranhas suck and they are nothing without a pack.this leads me to believe that they are skittish beccause they arent in a group. in the wild they travel in numbers of 25+. in our home aquario we only have about 8-10 on the average. so you go figure, a dramtic reduced group number in a new surrounding. i would be scared too. last note, piranhas are very misunderstoood. not the predatory fish the media describes it. there are far more things in the amazon that would take them out and are more bold in personality.

 

[CKY]

I think your right "o snap its eric". But then again if they were born in captivity being in small numbers would be normal to them.

 

[o snap its eric]

its in their genes? im guessing. take it like this.... your family was born in the wild for multiple generations correct? suddenly your switched into a civilized place. then you eventually have babies in the civilized place but you still have the wildness in you; and so does your babies. most piranhas that are bred in capitivies are 1st to 2nd generation. i think hitting 5-6th generations will dimminsh the skittishness a bit more. i dont know if i explained this good enough but yeah.....

 

[RhomZilla]

its in their genes? im guessing. take it like this.... your family was born in the wild for multiple generations correct? suddenly your switched into a civilized place. then you eventually have babies in the civilized place but you still have the wildness in you; and so does your babies. most piranhas that are bred in capitivies are 1st to 2nd generation. i think hitting 5-6th generations will dimminsh the skittishness a bit more. i dont know if i explained this good enough but yeah.....

Hmm.. good concept to contimplate on..

 

[Mr. Hannibal]

Not to worry normal behavior, still, don´t know why they do that!

 

[Xenon]

Damn I wish I could dig up the thread where Judazz explained the jumping thing....PM Judazzz, he knows why they do that, something about the gills.... I think piranhas are creatures completely dominated by instinct, thats why they are skittish and kill their tankmates!