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Agressive bristlenose

5754 Views 39 Replies 4 Participants Last post by  GCNZ
I have a 15 gallon planted tank which I set up about 4 months ago, the first fish to go in the tank were 8 neon tetras, followed by a small female bristlenose catfish, 2 weeks after adding the bristlenose I decided to get a male to keep her company, knowing I would soon be upgrading to a larger tank. since day one of introducing the male bristlenose the female has been extremely aggressive towards the male, if she gets sight of him she will chase him around the tank, away from food etc.
It's been afew months now and the fish all seem healthy but the female is still aggressive towards the male, and she is growing at a faster rate than him probably because she is dominant over the food.

Has anybody got an explanation for this bahaviour? The only thing I can think of is not enough room for 2 of them in a small tank, there is plenty of driftwood and plants, but maybe the female thinks she rules the place since she was there first...

I have now setup a 40 gallon tank and have transferred the male into this tank on his own so he can get some confidence back and get a good feed all to himself to try put on a bit of size before I introduce the female and the neon tetras to the tank with him.
Hopefully the female will leave him alone this time since they have alot more room now...
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Looks like a BN to me.

I find that BN's can become aggressive if they aren't getting enough to eat, but sounds like she's just territorial which I also find is pretty normal. I wouldn't worry about it much if he's getting enough to eat too. Or you can take her out and rearrange things so she doesn't have a territory anymore and see if that helps when you reintroduce her.

Also, BN's don't get their bristles until around 4 inches so you could potentially have two males in the end.
Look up green dragon BN pleco.

Clowns have definitive stripes, this one does not.
There isn't something 'wrong' with her, she's just aggressive is all. Some fish are and some fish aren't. I personally wouldn't worry about it since she isn't attacking him, as long as he's still getting food he'll be fine until he's more comfortable.
Idk, I've had females and they've all been more aggressive than my males.
Yes, one of them. Goes to show you that not all fish act the same even if they are the same type. I also have one at my LFS who has to be away from other BN's because she's too aggressive.

EDIT: and it wasn't just to other BN's either, mine was tail slapping any fish that got in her way.
No, the aggressive one I had since she was an inch and a half, so basically a baby.

It's not really weird, especially if you take a look at the wide variety of Betta personalities, some are super aggressive and others couldn't care what you did to them as long as they get food lol.
I know but again, you can't judge all of them just because some of them are what you would deem "normal" is all.
I do agree she is beautiful, it's a shame you're in NZ otherwise I'd take her! lol
Well that's good! As long as he's getting enough food, they should be fine. But as always, just best to keep an eye on them when you can, but I don't think she'll be too much of an issue once they both settle in finally :)
Oh lol!! That's pretty funny, well hopefully she'll learn a lesson from all this ;-) good luck with the new loaches! They sound like a hoot!
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You've got plenty of room in the tank. What's the footprint of the tank?

You could bump up your Neon school to around 10-12 and add a centerpiece fish like a Dwarf Gourami or something nice ^_^
Looks good! But yeah, I definitely suggest bumping up your plant stock, it will make your fish feel more safe and thus in return, your female BN might not feel like she completely owns the tank if there are "walls" of plants up, you know? But so far so good it looks like :)
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