Please explain what you mean by "each generation".Each generation of clown loaches have been turning out more and more weird.
If in fact CL's were being bred in captivity via hormones, the parent stock would be older loaches, meaning they would be wild stock. All offspring from such breedings would be F1. It's not like there would be several generations removed from the wild producing fry, as in F2-F10 specimens.
Back in 2009, when Ewurm made that comment he was incorrect. At that time, there was no mass commercial breeding of clown loaches taking place here in NA, or overseas. IMO, there still isn't. Not because of the cost of hormones, in Malaysia human chorionic gonadotropic (HCG) hormones have been used to induce spawning in various species of fish over the years, and as one can see by the prices in the link to Argent Labs it's not exactly expensive. In Malaysia 10,000 units probably cost less than a pack of cigs.
It's not the cost of the hormones that makes this type of breeding non profitable for farmers, it's the labor & time involved in these types of breedings. Just to get things going these hormones have to be intramuscularly injected into each individual female. Then with clown loaches one has to factor in their growth rate before they can be taken to market.
Did you see the pics that I posted of the farm bred clowns? They were teeny-tiny, 3/4" TL, in 40+ years the smallest that I have ever seen, and cost $13.33-$17.25 depending on quantity purchased. No one is willing to pay those kinds of prices for CL's that are not even 1 inch in total length. That's insane, and farms cannot compete with importers that bring in 5,000 2-3 inch pieces at a time, and sell them for a fraction of that amount. They are also very unstable at those sizes, and most if not all of those F1 loaches died before being sold.
At the wholesale level CL's are dirt cheap, 3-4" CL's cost as little as $1-2 US in Indonesia. Even with freight costs added on, one can pack a lot of juvie CL's into a decent size box that will only cost $50-75 (for shipping) landed here in NA. But even if one is the average LFS, that doesn't import themselves, but buys through local suppliers, decent sized CL's are still usually only a few $ a piece. Most LFS have a min of a 100% mark up on fish, many 150-300% mark up, so just keep that in mind when viewing store prices. So why would any store in their right mind pay $3-5 for a 1" clown loach, when they could get one 2-3 times that size for the same price?
IMO that's why commercial farming of these fish has never taken off, and I suspect that the farmers in Florida learned this the hard way. If there was $$$$ to be made, the Asian farmers would have been all over this years ago. Hormone induced breeding is certainly nothing new in Asia, they have been doing this type of breeding for decades.
There are different collection locations in the wild, and the CL's from Borneo (Kalimantan) do look different than those collected in Sumatra. They are actually genetically different fish, which may explain why some people are seeing different looking loaches from time to time.
I'm afraid I'm going to need to see some solid proof of commercial breeding taking place, before I buy into the possible increase in oddball loaches in some areas (if that's even statistically factual) being caused by hormone induced commercial breeding.