I currently have four myersi cichlids in the 7 to 9 1/2 inch range that I have grown from 2 1/2 inch range.Mine have proven to be highly aggressive to each other.I had my biggest male in a community setting and all was good until he got big enough to challenge for top spot and then he attacked a 11inch snook relentlessly until he had to be removed.I have a 7 inch female in that tank now and she gets along well with the others. I have a pair in a 125 gallon tank that I have been trying to spawn but so far with little luck.The last time I removed the divider I thought it may happen because female breeding tube was out and they were cleaning a rock but after about 5 days of this the male had banged her up so bad that I was forced to put the divider back up.Friday I removed the divider again and so far so good so I am keeping my fingers crossed. I know alot of what I have said sounds negative but I love this species and has become one of my favorites. I think you can get them to live peacefully in a cichlid community if the tank is large enough with a good mix of other large cichlids but I wound not recommend putting two Myersi in the same tank especially two males or you are asking for problems. Click on jweav and go to my threads and you will see that my big male has turned into a real glass banger and is very interactive with me and they are all big eaters.As for max size my big male has grown quite a bit from my last video and I would say is close to 10 inches now.I have read they can get to at least 12inches and seeing that mine I have had for only a year and half and that 12inches should be possible.Their beautiful cichlids and alot of fun to own.I hope this helps.