Hybrids almost never happen in the wild. Fish can tell who is their same species. But in our tanks or commercial breeder pond fish will breed with a "close enough" fish, usually the same genus but sometime a near enough relative to produce fry...whether they can reproduce can be iffy.
Varieties of a species are usually just line bred for color or fin shape etc. Line breeding (inbreeding) can lead to weaker fish. But those newish "electric blue" cichlids sound like maybe something else. It's not clear just where the "electric blue" gene comes from. I'm not a fan of albino, lutino or long fins etc. Those traits are fairly easy to breed for. I usually prefer "natural" fish except maybe for discus & angels
but I don't keep those anymore. I think that where NoodleCats borelli come in. They & your borelli are different...regional differences? Line breeding? Different tank lighting? I don't know.
& then there are the unscrupulous "breeders" of what I think of as "frankenfish". As I'm sure you know sidthimunki loaches are commercially bred using hormones & stripping out eggs & milt. Clown loaches are being created that way now too...but so are "tiger clowns" & other possibly attractive "new" loaches (my big negative focus).
I think now that DNA testing is less novel & expensive we might learn more but it may be too late to stop. & yes, the "Czech" & other fish breeders seem to have a reputation for hybrids with loaches but likely other fish too. But once 1 can breed a certain fish it's not long before many can & do.
Varieties of a species are usually just line bred for color or fin shape etc. Line breeding (inbreeding) can lead to weaker fish. But those newish "electric blue" cichlids sound like maybe something else. It's not clear just where the "electric blue" gene comes from. I'm not a fan of albino, lutino or long fins etc. Those traits are fairly easy to breed for. I usually prefer "natural" fish except maybe for discus & angels
& then there are the unscrupulous "breeders" of what I think of as "frankenfish". As I'm sure you know sidthimunki loaches are commercially bred using hormones & stripping out eggs & milt. Clown loaches are being created that way now too...but so are "tiger clowns" & other possibly attractive "new" loaches (my big negative focus).
I think now that DNA testing is less novel & expensive we might learn more but it may be too late to stop. & yes, the "Czech" & other fish breeders seem to have a reputation for hybrids with loaches but likely other fish too. But once 1 can breed a certain fish it's not long before many can & do.