If varies between species, some species finding the gender is easy and some is nearly impossible. Lots of species have a difference in color of the dorsal fin (the fin on the top of the fish). Others will have color variations elsewhere. Some will be bigger than others although this is not very reliable as one can just be older than the other. A sure way to tell the gender is which one lays eggs. Betta Fish are easy to differentiate the genders because of the fins and colors. It really depends on what species of fish you are trying to find the gender of.
Female fish are always bigger than the male fish. The male fish is usually also more attractive.
That depends on the species of fish. With some, such as guppies, it is fairly obvious, but with others, such as angelfish, it can be difficult to tell. Also, the rule for one species does not always apply to another; for example, males can be smaller than females, larger than females, or the same size, depending on the species.
the females are generally bigger
In order to know if a Silver Arowana is male or female, you need to look at the size of the fish. The male fish are bigger in size.
If the fish is male it will be bright and colourful, if it is female it will be quite dull
male is huge and grey female is colurful
What exactly is a fish coin?
flowron
the rosy red fish is the boy.
the female beta fish is "plainer" than the male as where the male is a darker shade near the face and lighter shade near the tail.
they females are brighter and the males are paler
The males have a red tail.
Your betta fish is a female if she has smaller fins than an average male.
If it tries to pinch you it's a female if it's calm and doesn't pinch you it's a male
Feeder fish, How do you tell male from female of the?