Time for a bigger tank

#1
Right now i have 6 cichlids in a 25 gallon and it is time to put them in their final home. I was wonder what would be the best tank to house these fish for the rest of their life. I have a 55 gallon but im thinking that they would need something bigger. The 75 gal listed below is getting stocked soon and so is not an option for my cichlids.
 

#2
I have a Red Devil and a Convict in a 55 gal. They get along as long as there are just the two of them. At least for now.( both around 5 inches)_ When I had to put other fish in there because my other tank broke ...it was not good. As they get bigger I don't know if the 55 gal. will even be big enough for the one Red Devil. (they can get to 13 inches and very aggressive) I'am at the point where I must get rid of some fish just to make room for their aggressiveness. I think if you get rid of your red devil your other fish might be fine in a 55 gal. but it would be full.
 

#7
I would say if you want to keep those fish together your best bet would be a 150 long. Do you have a male or female Red Devil??? I have two females and had to separate them. When the female spawns she lets no fish near her!! I try to put her to one end or the other by locating my decorations. The first time she spawned on a big rock in the middle of the tank and that was a mistake. She attacked everything around her and sent ALL the other fish hiding. Now I put a clay pot in the end of the tank for her to lay her eggs. That way the other fish can aleast enjoy the other half of the tank.

My Red Devil is my favorite fish. Sorry the picture isn't the greatest.