Brother/Sister form a pair..

[barrowkwan]

Could that cause any abnormal offspring? or better separate this pair ?

[Peachtree Discus]

genetics can degrade if too much inbreeding occurs. also consider - were their parents bro & sis.

[John_Nicholson]

You are more then likely fine. Almost all "strains" were developed though inbreedin/line breeding. Every PB in the world goes back to one fish. This is not 100% correct, but it will work for out discussions here...If a pair is unrelated that can be considered generation F0, their offspring are F1's, if a sibling pair develops their offspring are F2's, if a pair forms from the F2's they are F3's.........You can see how this works. I use to breed out to about F4's and then cross in new blood, but many breeders when trying to develop that new hot color that everyone wants will breed out much, much further then that, like F20. The trouble/benefit with doing this is you concentrate both the good (desirable) and bad genes. If your fish are nice healthy fish then I would not hesitate to breed them.

-john

[alpine]

As was told by someone I respect , don;t worry about after the seven generation .

Roberto.