Do discus fish not grow due to some kind of hormone?
There is considerable controversy as to whether smaller Discus grow alongside larger Discus. If they don't grow, is there some hormone released by the larger fish that prevents the smaller ones from growing? My non-scientific experience is that about 90% of small fish don't grow alongside larger fish, I'm obviously talking about Discus. Based on my empirical view from 43 years of experience with Discus, and after talking with some biologists, they are adamant. Yes, in Discus there is a hormonal and social phenomenon that may contribute to dominant Discus growing faster and "subordinate" Discus growing more slowly, as I observe. But scientifically it's not proven, so it's not correct to say that there is a single hormone that simply "prevents" the smaller ones from growing. However, there is a hormone called Cortisol, which we will discuss in another article on this blog, and it may influence the growth of smaller Discus. However, in Symphysodon...
