Discus fish buying

Question
Hi! I am just about to go and buy some new discus fish for my tank/s in a day or two. But I am wondering if it is really sensible as one of my discus that I all ready have is a bit of a picky eater.
I have a dilemma because I need more fish to made a group of a decent size for my three discus fish and we suspect that the picky eating may be a result of my picky discus (Coalbolt) not eating some foods.
On the other hand, we have almost got Coalbolt eating the cheap foods and suspect that it may be a matter of days or couple of weeks till we have him/her eating flake food. He/she will eat bloodworm and veg like courgette but refuses to eat flake food. We have  been offering him/her nothing but flake food and it seems to be working and he/ she is starting to eat it because she has nothing else to eat.
Unfortunately, all three of my discus are in solitary confinement as they do nothing but squabble when we put them together. Well, Coalbolt tries to shoal with the two others but they just attack him/ her. We found out that this is because the discus are insecure and need more in their shoal.
I think that we should get two or three more discus. That could make Coalbolt eat properly and sort the major squabbles between the other two.
My mum thinks that we should wait till Coalbolt is eating properly till we get more discus as adding more may break the 'weaning' on to flake food.
All of the discus can see each other and Coalbolt has a mirror so he/she doesn't get lonely.
I can't decide what to do as we need more discus but this may be a bad thing as well as a good thing.
What should I do???? Buy lore discus or wait till Coalbolt is eating flake food with an appetite??
Sorry if I don' reply as I don't have access to my email account. So thanks for the answer!!!!

Answer
AJ,


   As for the picky eater, just keep feeder her the food you want her to eat and she will soon realize that that is whats for dinner. As for adding more to the tank, as long as the tank you have now is no less than 60 gallons then you should be okay. Discus fish need a minimum of 10 gallons of water each. With the added fish, your picky eater might get better since there will be more fish in the tank at dinner time and will learn she better eat fast. If after you buy the other fish and Coalbolt is still not eating well, put her in your hospital tank and try to get her to eat there. We do this because she will be the only one in the tank and it is easier to work with them one on one. Of you have any more questions don't hesitate to ask. Good luck.