Long Fin/short fin

Hello,
I am new to the forum and am enjoying what I have read so far. I have a question which has bothered me for many months now concerning the genetics for the fins.

I read that the long fin gene is considered to be recessive which I had agreed with when I first happened to find my albino long fins had spawned. They were spawning every 2 weeks and all the fry had long fins. Now when they spawn I am getting short finned albinos too. I don't no what to make of this.

My study of genetics with rabbits, guinea pigs, cats, and hamsters all say to obtain the long hair, both parents must have or carry the long hair gene which would make the gene recessive.

So breeding the long finned plecos, I assumed the fry would all be long finned.

I noticed something else but I do not know if this plays into this gene of not. It seems to me the normal bodied albinos I am getting seem chunky, rather short bodied in comparison to the albino fry.

Can anyone explain? Or do I have a pair of unusual fish?

Welcome to the forum

Here is a good spot to start when it comes to genetics of the bristlenose

http://www.bristlenoseworld.com/t2500-crosses-interbreeding-bristlenose-updated

The genetics of the fin length is far from settled and as far as i can tell without a detailed genetic analysis it will never be. The problem is that there are general rules that apply 90% of the time but then you get the odd one that totally throws a spanner in the works.

In terms of chunkyness, that sounds to me like a trait (like I'm taller and broader than most people, while my cousin is short and a bit weedy).

There seems to be a lot of debate on whether BNs follow standard Mendelion genetics or not.

As for the "chunkiness" it may be an optical illusion. I have a LF common male who I swear seems slender and more sleek compared to my SF albino but actuality it's just that his head isn't as wide...I think the long flowing fins trick our eyes into seeing length as opposed to short fins that flatter girth. But who knows, maybe your guys are chunky and mine just have huge heads, lol!!