Originally Posted by Bombalurina
Wierd, I've always heard that 40 litres should be the breeding tank, with 2-3 80 litre grow-out tanks.
The reasoning given in the book is less stress for the male - a smaller tank means less space to "lose" eggs and fry, and is a smaller space for him to patrol to protect the nest. Looking around online also shows that breeders here discourage anything over 20l for the breeding tank, saying it encourages the males to stress out and eat eggs and fry.
I guess that the multiple smaller tanks for grow out is to make it easier to monitor them? There is talk about reducing the numbers in a tank and keeping the more aggressive ones apart from each other being better for growth.
I do think Japan takes it's fish more seriously in general
I live near the largest goldfish breeding locations (pretty much half the town is goldfish breeding pools). People take them very seriously...
But I think they also keep them in smaller tanks than what is accepted in the west. It is considered fine to keep fancy goldfish in a relatively small tank as long as they are well filtered and fed... And people do have beautifully healthy goldfish in smallish tanks and ponds.
They do sell bettas in cups here, but I have never seen any dead or even sick. They are always in crystal clear water, usually sitting on a large heating pad - even the cheapest veil tails. You see them more in small plastic cases (like the kritter keepers talked about on here), with the fancier in their own aquariums.
I guess that the standard for fish shops is just higher or something... I have yet to run into someone who gave completely wrong info. Even in the chain places they always know what they are doing, and if they don't they will look it up for you. Like when I was finishing up treating my goldfish for ich, I wanted to know if snails they had on sale would tolerate the slowly decreasing salt in the tank - and they didn't know and actually contacted the snail supplier to be certain. :D