Some fish show no visible differences in the sexes while in others the differences are very large and obvious. It all depends on the Genera and species of fish and sometimes also the sub species.
what species of fish? every one is different. some are very easy like guppies, some are a little more challenging like tetras, and some are completely impossible such as Oscars.
if its a goldfish, you can't sex them until they're over a year old and only during the spawning season in spring, males develop little white pimples on the gill cover.
there are a few oddballs, the amazon molly (not the black molly or sailfin molly you see in petstores), the entire species is female, no males at all. and some species of Saltwater Fish such as some clownfish and anthias can change from female to male if not enough males are present.
You need goldfish that are at least 2 years old
(That's when they are old enough to mate).
You can tell most easily when it is spring, and the male goldfish have small dots on their fins. They mate in the summer.
Also, female goldfish tend have more livid colors than the male goldfish. This is not true for all fish.
If there happens to be a male and female goldfish in the same tank, the male chases the female regularly and appears to attack it.
The sex can't be known in some species except by internal inspections.
can you tell if a fish is a boy or girl by the tail
A girl Betta is dull and not as pretty as the male. But, a boy Betta is colorful and pretty to attract the female mate.
You can tell the difference between male and female fish by a female wouldn't have as colorful gills as a male would or if you still can't tell the female would be a slight bigger than the male
no one
you can tell by the dots or spots on the boy fish and on the girl is just a gold fish colres
yes of course fishies are so totally awesome
Fish have scales. Seals are much larger than fish and have a slippery body and a little face :)
Lyre tail is simply a description of a fishes tail. What kind of fish is it? It will be a Lyre-tailed something.
no one
Depends on the species, but determined from an opening near the fish's anus.
no a fish has the memory spam of 3 seconds if it tells itself to stop eating it won't remember to do it
if on top of a parakeets nose is blue it is a boy if pink or white it is a girl.