Angelfish getting aggresive is pretty normal, unless one is getting hurt, or prevented from eating or the harrassment never ends then i would just put it down to normal behaviour. 110 litres is on the small size for angel fish, is there plenty of room for them to avoid and hide from each other?
Are you sure they are both female? Mine tend to fight just before they spawn, although its not unheard of for 2 females to try and spawn. 2 of my angels (m/f) are going at each other right now, so i expect eggs in the next day or so. They will then be friends while they look after the eggs for a couple of days at most before they eat them. Then a couple of weeks of peace and the whole process starts again.