that fully out breeding tube says that its a female and shes ready to lay eggs, and thats the reason shes angry. if she finds some where flat or a pot, she will lay eggs there. they go very aggressive at this time and bite every thing around the breeding site.
They won't get fertilized if theres no male with her. unfertilized eggs will get white and decayed after 2-3 days, she may eat them to clean the position for next spawning or just leave them and other fish eat them, if not you get them out.
they can breed with RDs, midas, flower horns, trimacs, parrot fish and etc. they are all aggressive fish and even may kill their mate before or after the breeding. I won't recommend you to try to breed them except you have large tank and enough experience.