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telling the sex of the common bristle nose

Featured Replies

  • HOF Member

Hi all I have 2 bristle nose plecos and wondered if the only way to sex them is that the male grows bristles. If so at what size can you tell.

One is about 6 cm and the other about 4 neither have any sign of bristles

Thanks

hello a bit to young should show signs around 7cm as for the 6cm and no bristle at all could be female can you post a pic and i should be able to tell you 4cm to small to sex what do you feed them

sorry 4 other fish not 4cm post a pic of them to

  • Author
  • HOF Member

I have a good mix of fish foods fed daily including algae wafers and cory wafers, several squares of moss for them to graze on, frozen blood worms daily and the usual cucumber, zuchini and other vegies. They are growing extremely fast will try and get a picture tomorrow -I'm borrowing a camera the iphone just isn't doing it for me!

Thanks

ok cool look forward to pics

  • Author
  • HOF Member

Does that diet sound OK it's a community tank so I feed quite a variety. They look fit and healthy. I got some clown loaches a couple of weeks ago and one of them was so skinny you could just about see his ribs, he has put on a heap of weight and just loves his blood worms and any snails I find in the shrimp tank.

when I had my bristle noses I never really fed them, but they were growing and breeding rapidly.

should be able to tell sex by 4-5+ cm

  • Author
  • HOF Member

I just had a good look at the bigger one and some bristles are starting to show do the girls get any bristles at all? I don't really know why I want to know I'm not really looking to breed fish they are just there to look nice in the lounge room. I just like to know lol.

no females dont have any bristle have you got a cave for them

4.5cm is a bit small to sex correctly

i sex them at 3-4cm..the best way i have been shown is by bigjohnofish a really awsome guy and great pleco beeder..

best way to do it ..is to catch them with a net and put them in your hand out of the water..

then you have to feel the top of there nose ...

if this section is soft and squishy it will be a male

if the nose region is harder to the touch it will be a female..

best way to know the difference is for someone to let you try on a mature male and fem.. then you will be able to know what your looking for..

or seeing if you have one that is starting to show bristles feel that one first as its most likely male.. then feel other one and see if it feels same or rougher ;)

hope that makes sense

and good luck

honcho :D

i no bigjohnfish dont think he would guarantee sex of fish at that size

no he doesnt when he sells them..

but when i go up there to get any bristlenoses we both have a go and pretty much are always correct ..

its kind of different when you have time to fool around and play fish ..

btw this method has been pretty good upto date and works for bristlenoses only..Longfin and shortfin..

no other plecos

  • Author
  • HOF Member

Thanks guys but if it means catching them I would need to pull the whole tank apart and as I'm not worried if they breed its not worth doing that. It's a big 215 litre tank. I have lots of tunnels , barrels and other hiding places including a large PVC pipe so if they are a pair and they want to breed they could find a place. I was more just interested in any visual clues. I read somewhere that bristles may not be one hundred percent indication as some females grow a small amount of bristles. Don't know how correct that is. In a way I hope they are not a pair as the last thing I want is lots of fry in my tank I can just imagine what hubby would say when I tell him I need more fish tanks I truly think I'm at my limit of spending for a while:)

Thanks guys but if it means catching them I would need to pull the whole tank apart and as I'm not worried if they breed its not worth doing that. It's a big 215 litre tank. I have lots of tunnels ' date=' barrels and other hiding places including a large PVC pipe so if they are a pair and they want to breed they could find a place. I was more just interested in any visual clues. I read somewhere that bristles may not be one hundred percent indication as some females grow a small amount of bristles. Don't know how correct that is. In a way I hope they are not a pair as the last thing I want is lots of fry in my tank I can just imagine what hubby would say when I tell him I need more fish tanks I truly think I'm at my limit of spending for a while:)[/quote']

females can grow bristles but only a few and on the top lip from left to right

males will get them up the ridge of the nose too..

although most females i have seen with bristles have been fairly old..

i no the method your using i do the same but its no 100percent

pretty much always right is not 100 percent guaranteed

dont want to get into an arguement about this as this is my opinion

i no the method your using i do the same but its no 100percent

pretty much always right is not 100 percent guaranteed

dont want to get into an arguement about this as this is my opinion

lol.. i never said anything about percentages..

if u use this method then you will know it is much better than waiting until they grow bristles and quite reliable too

lol you said you can sex at 3-4cm

i no it reliable but not guaranteed as you would agree

  • Author
  • HOF Member

I will try to get a picture tomorrow but I don't suppose it will prove anything then. Lol I've opened up a can of worms here

  • 6 years later...

Just found this thread when I was trying to work out how to sex my own calico bristlenoses. Spent a while trying to catch all 3 of mine to test them with the method mentioned previously. I have one 4cm fish that has a very hard nose and no bristles, a 5cm that has small bristles along it’s upper lip, and a 7cm+ fish that I couldn’t find nor catch. Sneakiest fish I’ve ever owned! Can anyone (if ur still active) let me know what they think the 5 cm is? (Photos below)

Cheers!

 

235EACD3-10F7-4ECC-BC75-F761CF3AF442.jpeg

940D41F8-4502-4C38-94BA-C5059E6EAD9D.jpeg

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