I bred my Discus a few times but it sure was a whole lot of work. Yes they needed a tank of their own and they took care of the fry. I never used a 'cone' but instead just had an Angelfish breeding slate leaning on one of the glass sides. They used that all the time. If you water is not very, that's "VERY" soft you may not get viable hatches. Good luck though as I have heard they have been breeding in a little harder water lately.