You say they are juvenille angels. How many do you have and what size tank? I usually do not notice this type of behavior in angels until adult size, about silver dollar body size or larger. The type of behavior you mention sounds like male's sparring or you may have a pair beginning to pair up. As mentioned this behavior is normal and as long as the tank is suffient size and you have hiding place's they should be fine.
Their body size is about silver dollar sized. I didn't realize this size makes them adults. I thought they'll get much bigger than this. I have them in a planted 75 and up until now... about a week... the 3 of them were inseparable
Use causion, they get very aggressive when a pair develops.
Sounds like it is time to break them up. I had them in a 65Gl tank and that didn't help, it looks like anything under 100GL doesn't help much.
And the males may do permanent damage to each other. I had two males fighting once the one male paired up with the lone female. The paired male injured the other male causing one of his ventral fins to tear off and it never regrew.
at this size domestic angles will often form pairs.
the lip locking is probably a male and female .
the ones that hit the sides are probably males fighting over the female/females.
Their body size is about silver dollar sized. I didn't realize this size makes them adults. I thought they'll get much bigger than this. I have them in a planted 75 and up until now... about a week... the 3 of them were inseparable
Many fish reach adulthood at a smaller size than is commonly believed. Although they have reached sexual maturity, many species will continue to grow, some times significantly, through out their lives.
The only way to be 100% sure of male and female is by the breeding tubes, when they are spawning. The female's tube is blunt and larger, while the male's are smaller and come to a point. Although not always accurate the males will usually have a pronounced hump on the forehead, this can usually be seen when multiple angels are in a tank and they are of adult size.