Not really no, they don't get a real hump on their head... though very old males sometimes do... very old and big.

A single male Steatocranus casuarius might work for you.

 

mine has a bit of a bump...not a hump though...

 

Well a male convict seldom developes a hump as large as a male Steatocranus casuarius would. And dependant on what you have already stocked in your 55 g, a Steatocranus casuarius may very well be a better choice for your tank (?).

But it is nothing unusual for a male convict to develope a nauchal hump.....though some never do. And they certainly don't have to be neither large nor old to develope a large hump, though I supose a very large hump is more typical of a larger and older specimen . I've had nauchal humps on smaller 1yr. old males that were much larger then the one on my current male con. Seen many on much smaller male cons that were a MUCH larger hump then on any I have ever owned.

My striped male at 3 yrs. of age (3 yrs. from being layed as an egg, not from being purchased---a fish from an LFS is probably already 3 months to 6 months old or more):

My 'pink' male con at a little over 2 yrs. of age (from being layed as an egg):

True both are large 6'' males, but I certainly don't regard either as 'old'. And as I mentioned already, it is nothing too unusual for much smaller and/or much younger males to develope nauchal humps that are much larger then either of my males. Though some never do.

 

Well a male convict seldom developes a hump as large as a male Steatocranus casuarius would. And dependant on what you have already stocked in your 55 g, a Steatocranus casuarius may very well be a better choice for your tank (?).

But it is nothing unusual for a male convict to develope a nauchal hump.....though some never do. And they certainly don't have to be neither large nor old to develope a large hump, though I supose a very large hump is more typical of a larger and older specimen . I've had nauchal humps on smaller 1yr. old males that were much larger then the one on my current male con. Seen many on much smaller male cons that were a MUCH larger hump then on any I have ever owned.

My striped male at 3 yrs. of age (3 yrs. from being layed as an egg, not from being purchased---a fish from an LFS is probably already 3 months to 6 months old or more):

My 'pink' male con at a little over 2 yrs. of age (from being layed as an egg):

True both are large 6'' males, but I certainly don't regard either as 'old'. And as I mentioned already, it is nothing too unusual for much smaller and/or much younger males to develope nauchal humps that are much larger then either of my males. Though some never do.

What do you have in the tanks with them? And what size tanks are they in?

 

What do you have in the tanks with them? And what size tanks are they in?

Gave the 'pink' male away just over 1 yr. ago. Striped male became intolerant of him---started to chase the 'pink' male around too much. They have same mother, different father; 'pink' male about 1 month older and they have been in the same tank pretty much all the time since they were young fry. 'pink' male was a 'freak' at a very young age----stood out as significantly bigger then his siblings at the fry stage and was absolutely humungus for a male con at 6-7 months of age-----but at 1 yr. of age, both males were of very similar size. They have been in 33, 100, 75, 125, but mostly in a 180 gal.

A few videos over the last few years showing tankmates:
180 gal., oct., 2007:http://s192.photobucket.com/albums/z116/Bern-C/?action=view&current=MVI_2006.mp4

125 gal., nov., 2008:http://s192.photobucket.com/albums/z116/Bern-C/?action=view&current=nov292008125gal1007.mp4

http://s192.photobucket.com/albums/z116/Bern-C/?action=view&current=nov222008125gal021.mp4

180 gal, jan., 2010:http://s192.photobucket.com/albums/z116/Bern-C/?action=view&current=IMGP1897.mp4 180 gal., oct., 2010:[url]http://...url]http://s192.photobucket.com/albums/z116/Bern-C/?action=view&current=006.mp4

As of yesterday, my male con has been removed to a 15 gal. hospital tank. Took a beating from the young male blackbelt :x Don't know if he'll pull through. Although the male BB is 1 1/2 yrs. old , he's still small enough to fit into the convict'[/url]s cave----and he managed to get in, and boot the male con out. It's not always easy to house male CA in the same tank, especially over the long term.