How Does A Bristlenosed Plec Show Agression?

[simon1985]

i have a lovely female bristlenose plec, 8 platys (2 only 3months old) 3 glass catfish, 1 guppy and 1 tetra something (one with a the big eye print on its sides) 4 ameno shrimps in 20 gallon hex tank.

The other day the plec was near the front of the tank like she sometimes is, but she was flexing all her fins and the barbs by her gills kept coming out, then she did something that was very strange, she started lunging forward, as if to spear.

Im not sure if this is her showing agression but it certainly looked agressive.

Oh, and the bristlenose in question is about 5inchs long.



A bit more about me and fish...
I was given this tank about 4 months ago, it had around 15 fish and when i got it home i only had about 20% water (Person that give me fish poured it away, too heavy to carry) and no gravel. so i put in new gravel, added 80% new water but most of the fish died over night. (they were old anyway).
So was left with 3 fish, the guppy, tetra and plec (she is about 6years old).
I let the tank cycle a bit with these fish, then added what is currently in there.
After a few problems everything is fine now, amonia, nitrits etc.

There is a hollow rock thing in there that the plec practicly lives in given to me with the tank, along with a proper rock. Ive added a fake plant and an air stone which ive been leaving on constently.

Im just curious as to why the plec has taken to doing this.


How would a bristlenose show aggression and what exactly was she upto??

Has anyone else seen the spines near the gills im taking about?? (they kinda come out like little white hands, but ive read their her weapons)

Has anyone seen their plec lunge in a spearing motion??? (she only lunged 3 or 4 times, but a few seconds later when another fish came near her she moved towards it making it flee away)

Or could it be the air stone is annoying her?

 

[bananasdoom]

I am just new to the forums and to fish keeping in general but after a bit of reserch the only refernce i could find on the net was on a another forum and it seemend to answer your question

Plecos are usually only aggressive towards other plecos. When they grow larger, they do not like having other fish in their path. When the pleco is the largest fish in the tank this can look like aggression, but it is really just going about it's business.

http/goo.gl/8cWZ5

 

[simon1985]

thanks for the reply.

have you got a plec?
have you seen the spines by the gills im talking about?

She shows them off quite often, usually with the fin on her back going up aswell. theres not alot about in on the web, i just want to confirm other peoplpes plecs show these spines as well and to know that she's not distressed

 

[lilfishie]

i have kept and bred BN's in the past and seen these spines a few times, mainly where food is involved and there showing the other fish who's boss

 

[SusanFish]

This is normal, my Bristlenose's have been doing this especially when being moved to another tank. Occasionally they tend to "fight", but it's usually when new juveniles become adults and they simply try if the current "boss" is strong enough. However, they won't kill each other.

Another situation when they fight too often is an overcrowded tank - in such a case you'll see a lot of fights.