Interesting Fact About Betta Fry Growth

[constantine03]

I've been reading a lot of bettysplenden's articles (when really, I should be studying. I have two exams tomorrow...I need better time management skills), and ran across this interesting fact about betta fry and why frequent water changes are so important:

"Scientific studies have proven that most fish, including bettas, excrete a hormone that acts as an inhibitor to growth. In the betta community it has widely been said that this growth hormone stifles the potential of smaller fish in the spawn, giving the advantage to the larger, healthier fry. While this goes a long way to explaining the sometimes dramatic size differences between fry from the same spawn, it is my personal belief based on what I have read that this hormone actually works to limit the growth of the fish so that it does not outgrow its environment. In nature this would be a handy tool, ensuring that there is enough space and resources for all. In the spawn tank, it's just inconvenient. A couple of hundred young fish in a ten gallon tank will soon produce enough hormone to severely limit growth unless the water is changed, and changed often. I change the water in my growout tanks at least 50% every single day. Other successful breeders have reported changing as much as 80-100% per day, with excellent results."-- BettySplendens (Victoria Parnell)

Obviously I know water has to be changed to keep water levels in check, but I didn't know about this hormone. I wonder what the specific name of the hormone is, and what pathways it works through...seems very similar to growth hormone in humans, only works in the opposite fashion. It could be a handful of things though. Anyhow, just thought this was interesting

 

[modaz]

this is true for most fish esp livebearers, how often do you find so called "female sword" turn into a male and how many times do we see a thread on "my fish has changed sex", its typical of guppy fry too, for instance ive got 6 bottom sword juviniles from the same drop, the alpha male is in full colour and his tail is the length of his body, he's now breeding with the 3 females, the other 2 males are just starting to show some colour in the body and their swords havent even started to grow yet, i left this male in so that he wouls breed with the females as he is a yellow version of the strain and quite a new look and that the other males would stay small at least until the females are pregnant. the whole thing of your thread and the artical is in deed fact and a very interesting one too.

 

[sailfinman]

so that could be why everybody says a lot of times fish are proportional to their tank
and that could be why fish grow larger in the wild
i know im being captain obvious here but thats pretty interesting.