Evil Pleco.

[snowflake311]

I have had pleccos before but the 2 I have now are Female BN plecos and they are Nasy fish. one is in a 100 Gal and can't do much hard to the fish in that tank. But I have another mean girl in my comunity tank and she is very aggressive during feeding time. I had a clown pleco years ago that was a little crazy at feeding time. But this Pleco is Crazy she is out to get them. Chases them down and almost gets on top of them. she is really mean to the other catfish like the Cory cats and Bumble bee cats. She might have been the cause of the death of my older Loach because living with this pleco around must be stressful on the other fish. 
 
I am thinking I am going to rehome it she just keeps getting nastier and nastier. Anyone have any evil plecos. My first Female BN was the best fish ever never was this aggressive. 

 

[Akasha72]

I had two male BN's in my tank and they lived happily together for a number of years then one Sunday evening, whilst I was cooking my evening meal, I looked at my tank and there was sand flying everywhere. The fish were hiding in plants and corners utterly petrified. I got closer to the tank to see what the problem was and my BN's were fighting 

 Both had there cheek spines flared and they were using them to knock hell out of each other! I was horrified. I tried to break them up but they just kept coming back and attacking each other. I rang my Dad in utter panic as he's kept fish all my lifetime (over 40 years) and he said he'd come to my flat and see if he could help.
We ended up catching one and he took him home to his tank for the night. Dad's tank though is only 2ft and not really big enough for a full sized BN and so in the morning I went to Dad's to help re-catch him and he had to go to the lfs. My lfs re-homed him within a week or so ... I did warn the lfs that he was not to be kept with another male BN and explained what had happened. He went to a community tank as far as I'm aware to a lady who was experienced (this is what the lfs told me) so all was well that ended well ... but, yeah, never again. I'm used to cichlids but the aggression between those two boys was way worse than any cihclid I've kept!

 

[Ch4rlie]

Wow.
 
And here is me thinking Plecos are a peaceful fish specie......
 
To be honest, I have not come across anyone ever saying their pleco is aggressive and could be bullying at feeding times. A new one for me to read about. 
 
Was this pleco aggressive when it was smaller / younger?
Perhaps when they become fully grown they change behaviour?
 
Would be interested to hear if anyone else has had similar experiences with their plecos.

 

[Akasha72]

that was my experience Ch4rlie, as they matured their behaviour changed ... two adult males in a 4ft tank was just no good. My pair were hell bent on fighting to the death 
They were two differing personalities though. One was docile the other was a tank bulldozer .. he was quite destructive .. bordering on mildly aggressive. No guesses on which of the two I kept!
 
I checked in with the lfs the day after I left him there and they'd come into work the next morning to find all the substrate piled in a corner and the piece of wood they'd given him to sleep in moved from where they'd left it! They said to me 'you wern't wrong when you said he was a bulldozer!' 

 

[betta fish]

I have had bristlenoses quite a few times and currently have an adult albino female in a mixed community never known them to be aggressive either, what do you feed her? is the aggression only during feeding? perhaps you can distract her with some cucumber or zucchini or maybe an algae tablet whilst you feed the other fish? not really sure what to suggest always known them to be quite shy.

 

[snowflake311]

This is not the first nasty pleco. I bought one for a friends tank and it would attach the cory cats. SO I took it home and put it in my 100 gal were it can't push anyone around because everyone in there is much bigger. Then I bought one for my 80 gal planted tank. She was fine for a year now she is just the worst. 
 
It is mainly at feeding time when she goes NUTS. I have seen her get mad if a cory cat got too close to her. She gets fish food that falls, and algae wafers, there is algae in the tank for her to grave on. She is not starved she is pretty thick. This is not a small tank it is an 80gal. All the other plecos I have had were just pushy but these 2 most resent ones are down right scary. This one I have in the 80 gal is out to hurt someone. I will get a video.  
 
I am going to just drop her off at the LFS. 5 years ago I had the best BN Pleco she was peaceful and I just loved her. But I lost he I think to a long power outage in the winter time the water got really cold.  
 
This pleco hates to share anything thing she thinks it is all hers. 

 

[NickAu]

Your pleco sounds normal to me.
I have a mature male and female BN in a 6 foot tank,  my clown loaches  know to stay away from the male at feeding time, He even chases the female away from "his" food.

 

[Baccus]

By the sounds of it the worst aggression is around feeding time, and I am guessing that the BN usually gets one or two algea wafers where as the corys tend to get pellets or wafers designed more for them.
The main times I have seen any aggression from my adult BN's has been for the catfish wafers, BN's love (and need) some protien in their diet so if the protien type foods are slim on the ground then the BN is going to defend what it needs in its diet. Have you tried scattering the catfish wafers and possibly a couple of algae wafers in different parts of the tank? I find with the food being scattered along the length of the tank, anyone like a BN that can "hog" an entire wafer/ pellet will stick to the first lump of food they come across, allowing the other fish in the tank to locate and eat the food at their leisure.
The only other time I have seen aggression is again with food and juvi growing out BN fry that are all striving to get as much food into themselves as possible. And considering that there can be any where for 50+ fry in a particular batch of eggs, no wonder they are all ready to fight it out for food.
You mentioned that your female is quite "plump" which I would suggest is that she is full of eggs and ready for breeding, if you have room a mature male BN might subdue the female a tad and she will be kept occupied being wooed by the male until she actually lays the eggs and he takes on all parenting duties.
 
As Akasha72 found out two mature males will fight and they can be pretty violent towards each other. Two mature females with only one mature male can also go into battle for breeding rights and have the male guard their eggs and young. I have never had any issues when only one pair of BN are kept in a community tank, or where a solo BN is kept again in community tank, but is given access to all types of food including catfish wafers as well as algae wafers.
 
* When I say "pair" I mean it in the true breeding sense of the word i.e. 1 male and 1 female not just a pair as in 2 be it any combination of male/ male or female/ female as some petshops will sell things as.

 

[NickAu]

 
BN's love (and need) some protien in their diet

Yes, and they also need vegetables, sadly all too often they are sold as algae eaters with the words " No you don't have to feed them " 
 
I feed my BN's Xtreme catfish scrapers they love these, So do the Clown Loaches, and my Shrimp and the Tetras and my Kuhli Loaches, Even my Bettas have a pick at them.
 
http/shrimplovers.com.au/product/catfish-scrapers-125g-sinking-wafer

 
Ingredient List: 

Krill Meal, Shrimp Meal, Fish Meal, Herring Meal, Squid Meal, Octopus, Green Peas, Rice Meal, Wheat Flour, Distillers Dried Grains with Solubles, Spirolina blue-green algae, Stinging Nettles, Brewers Dried Yeast and Paprika.

 
When I feed blood worm I always tuck a few extra bits in the males cave.

 

[Far_King]

I had a couple of Sailfins from when they were half an inch or less in size.  They used to spend all their time together in the tank until they got to around 7".

That's when the trouble started.  One day they just started spinning around and knocking the stuffing out of each other and stressing the other fish.  As soon as one got his pectoral fins torn I knew it wasn't going to end well.  I re-homed them both in the end to friends of mine with large tanks and no plecs.
 
The plecs I now have are Gold Nugget and a BN in separate tanks.  I'd rather keep them like that just in case, although I suspect I actually had two males when I had the Sailfins and as they matured they no longer tolerated each other.

 

[Akasha72]

on the subject of food, for UK members try New Era (recently changed name to Vitalis) plec pellets. My BN loves em, as do my cories and SAE's. I get the large pot which costs around £12 and I cut the pellets in half. They last me ages and they appear to have good ingredients to cover their dietry needs