If you have prettier fish than it in the aquarium, he could be jelous. I know from experience. Or before he was in your aquarium, he sould have been in an environment with more aggressive fish than him, so that made him more aggressive. If you wanted, you could by a net breeder and put him in it if he will fit. That's how I calmed down mine. Just every time you see him chasing the other fish, just put him in it for about an hour (underwater of course!). He should start to calm down. Just MAKE SURE you DON'T leave him in for to long, or he could get really sick.
No, it is not possible for a Dalmatian fish to become pregnant as fish reproduce through spawning, where eggs are fertilized externally.
It is generally safe to keep a pregnant Dalmatian Molly in a community tank with other fish, as long as the tank is well-maintained and the other fish are not aggressive towards the pregnant fish. However, it is important to monitor the pregnant fish closely and provide a separate breeding tank if needed to ensure the safety of the fry.
They are your fish. You name them.
If there are fish small enough for the molly to swallow in the tank with them then they will most probably be eaten. They will eat their own young.
a mlion
It is a risk. Every fish you put in a tank has a risk of fighting
It is defending it territory.
Some fish are aggressive when it comes to food. The fish may simply not have enough space, the fish they are chasing may be pregnant, and the others are chasing it in order to get her to "drop" (have the fish babies) or the fish they are chasing may be sick and dieing.
no i have black molly if you have guppes thay will go with it and otherr fish
Betta are social fish. There is nothing wrong.
lay eggs
One goldfish chasing (or in this case biting) another fishes rear is how goldfish flirt, however this could also be a display of aggression towards the other fish.