red spotted gold severum

My Red Spotted Gold Severum and Green Severum have attempted to breed and laid eggs on 2 occasions. Both times, the eggs remain what I understand to believe as fertile and I make sure to have all perfect water parameters/water flow. I've heard they need a few rounds sometimes in order to get it...

I have been reading up on gold severums today and at this point I am thoroughly confused. I should go back to 10th grade biology again and re-learn what I once knew about dominant and recessive genes I guess. What is the best approach for attempting to establish a breeding pair of severum that...