Lol. No. People, no.
Inbreeding is all about chances. You will not 'get bad quality' or 'mess it all up' or 'produce magnificent fish' in '[insert-random-number] gen'.
As you probably know, the first gen resulted in very similar fish. This is because the offsprings all are exactly half Jag half Loseillei, and whilst there are individual differences brought about by different alleles of the same genes, most are more or less homogenous. And therefore the F1 purebred x purebred is relatively similar. Of course there are some differences, but yeh.
Anyways if you inbreed them you'll get a large variety of offsprings, because now you can have all sorts of combinations. It is possible to have some with heaps of Jag genes and few of Loseillei-ness, or vice versa. And so you'll see heaps of varied traits.
Now, this is an entirely stochastic process, and so basically there's no hard and fast rule to it. In one batch all the fries could be defective. Say either the original Jag or the Loisellei was het for a defect, it is possible that both of your hybrids is het for it and happens to produce and entire batch with is homozygous for the defect. But then in the next batch, maybe none will.
And maybe, possibly, out of 1000 fry that you grow out (hypothetically), ONE looks absolutely STUNNING because it has the PERFECT combination of genetic elements from the parents.
So it's all up to the chances. There is no definite 'you will find heaps of defects in xyz generations' or the likes. You definitely could, but by the same token, you might not see any for 20 generations on.
With purebred species usually people selectively breed for some sort of specific trait without any regards for any other traits, and so even when more and more defective fry turn up they still breed on anyways for the better color or shape or pattern or whatever. Sometimes it's just that a mutation cropped up and is ignored and so it just keeps on spreading about, or certain defects are associated with whatever is being selected for in particular - could be due to the same genotype, or could just be genes linked together due to being close to each other on the chromosome.
With (F1) hybrids (of two purebred species), the subsequent generations when inbred will still have heaps and heaps of variation, and so you will see all sorts of quality goin' on, and so it's quite different from inbreeding purebreds. What 'you' are aiming for is to keep on choosing the 'best quality' offsprings and breed them to fix said qualities. 'Best quality' in parentheses of course, because a lot of it is subjective.
Anyways yeah. Basically, your F2 and onwards will be hugely varied. They can be defective or perfectly fine. They can be completely awesome or absolutely ugly. Chances is you'll get a good mix of 'em all. Though I doubt you'd get a really nice lookin' one right off the bat. But hey who knows.
Keep in mind all the traits from the parents that you can see in the F1 are dominant ones, the recessive ones are the traits from the parents that you can't detect.
Basically.
Inbreeding is all about chances. You will not 'get bad quality' or 'mess it all up' or 'produce magnificent fish' in '[insert-random-number] gen'.
As you probably know, the first gen resulted in very similar fish. This is because the offsprings all are exactly half Jag half Loseillei, and whilst there are individual differences brought about by different alleles of the same genes, most are more or less homogenous. And therefore the F1 purebred x purebred is relatively similar. Of course there are some differences, but yeh.
Anyways if you inbreed them you'll get a large variety of offsprings, because now you can have all sorts of combinations. It is possible to have some with heaps of Jag genes and few of Loseillei-ness, or vice versa. And so you'll see heaps of varied traits.
Now, this is an entirely stochastic process, and so basically there's no hard and fast rule to it. In one batch all the fries could be defective. Say either the original Jag or the Loisellei was het for a defect, it is possible that both of your hybrids is het for it and happens to produce and entire batch with is homozygous for the defect. But then in the next batch, maybe none will.
And maybe, possibly, out of 1000 fry that you grow out (hypothetically), ONE looks absolutely STUNNING because it has the PERFECT combination of genetic elements from the parents.
So it's all up to the chances. There is no definite 'you will find heaps of defects in xyz generations' or the likes. You definitely could, but by the same token, you might not see any for 20 generations on.
With purebred species usually people selectively breed for some sort of specific trait without any regards for any other traits, and so even when more and more defective fry turn up they still breed on anyways for the better color or shape or pattern or whatever. Sometimes it's just that a mutation cropped up and is ignored and so it just keeps on spreading about, or certain defects are associated with whatever is being selected for in particular - could be due to the same genotype, or could just be genes linked together due to being close to each other on the chromosome.
With (F1) hybrids (of two purebred species), the subsequent generations when inbred will still have heaps and heaps of variation, and so you will see all sorts of quality goin' on, and so it's quite different from inbreeding purebreds. What 'you' are aiming for is to keep on choosing the 'best quality' offsprings and breed them to fix said qualities. 'Best quality' in parentheses of course, because a lot of it is subjective.
Anyways yeah. Basically, your F2 and onwards will be hugely varied. They can be defective or perfectly fine. They can be completely awesome or absolutely ugly. Chances is you'll get a good mix of 'em all. Though I doubt you'd get a really nice lookin' one right off the bat. But hey who knows.
Keep in mind all the traits from the parents that you can see in the F1 are dominant ones, the recessive ones are the traits from the parents that you can't detect.
Basically.