It is not fighting. It is competition.
The only difference is the tail is about 1 cm bigger Males usually aready have fancy tails i find
Male guppies have a pointier anal fin and a bigger tail than the female and the female is larger than the male.
sounds like you have a male guppy harrassing a female. Simply go and buy a few more female guppies and that way the male will have more than one female to harass.
The armillo uses his tail for fighting
Other fish with guppies it absolutely fine but some fish can get jealous. Well guppies like to show off their tail and sort of brag about it. So the other fish depending how aggressive it is, it may nibble of part of it's tail. And usually it won't grow back the same. Lot's of people wonder if goldfish will eat their guppies. Gold fish could eat guppies if they grow enough. Like if you get a fancy gold fish and it grows big then possibly. The size that goldfish grow depends on how much room they have. Like if a goldfish lived in a 50 gallon tank then it would most likely grow much larger. But if it was in a little bowl it probably won't grow as much. So most likely it won't but anything can happen. So pretty much it depends on what size tank you have. Well anyway you could usually have guppies with other fish. Just so you know Goldfish can't live with guppies because of their different water temperature requirements. Guppies can only live with other Tropical Freshwater Fish.
mine has a yellow+black spotty tail but they can be practicly any color
Gigan uses his tail for balance,swimming,and sometimes for fighting.:)
Colours on fish are often associated with their attractiveness to members of the opposite sex.
They were probably fighting with each other.
Guppies are livebearing fish, and so they've been bred in captivity so long and so easily that many different varieties have been produced including fantail, lyretail, veiltail and many other long/draping tail varieties. These occur in males and females. generally, the male's tail is larger, but if you compared, say, a male with a small-tail variety and a female of a veiltail variety, the female's tail would be bigger because she's been selectively bred to have the big tail. If you're trying to tell the sex of your guppies, there's an easier way. Guppies are livebreeders and use internal fertilisation, meaning that the male guppy has a penis-like organ known as a gonopodium that he uses to make the female pregnant. It's basically a modified anal fin and is located just behind the pectoral fins. A female with a tucked up anal fin can look like a male until you learn exactly where to look, it takes a while. the gonopodium points back towards the tail and is very thin. Males are often leaner in the body than females also.
If you were the smallest guppie, wouldn't you appreciate some consideration?
you either have a bad chemical in there or not a big enough tank