So apparently the Blue Rim is a crossing between a blue betta and a dragon betta, in a way such that the base colour is blue but the dragon mantle exceeds into the fins and causes the rims.

So this means crossing a blue with a blue rim will yield several interesting results.

One result could be a full blue betta, since both bettas have a base colour of blue.

Another is a blue dragon betta, which is really cool, but rather rare it seems

Of course you could have some blue rims.

You could also achieve a somewhat marbled pattern, as sometimes the dragon mantle don't cover the betta evenly.

Full white or 'Milky white' where the mantle spreads fully to the entire fins.

Of course this is vry broad, and realistically due to so many alleles in bettas controlling colour, scale pattern and fin shape, you'll probably get a skittles selection of bettas

 

Ok very interesting. Thanks for the info!

 

Blue rim = should be marble related dragon
Blue = regular irid base color (dominant)

Dragon x non dragon = partial dragon
Blue rim x blue = mostly blue partial dragon, plus what ever hidden genes the pair carries. few if at all, perfect blue rim

 

Ok thanks, and also what about the chances of the fry getting the HM genes from the female, because the male was a PK?

 

I need to see a pic 'cause I cannot vision the description blue-rim.

Nevermind, I got it. The body and fins are solid same color, but the edges of the fins are a different color.

 

Long fin is dominant over short fin. If both have caudals that spread 180°, you should have many with such caudals.

However, the side effect of the cross will make many have longer anal fins. You need to breed further; either towards long, in between, or short fin - all with their own specifications.