I have 3-4" red, 1-3" gold and 1-7" green all in a 125 gallon with other small 2" leopard. Well the only problems is that during feeding time the bigger ones tend to be more aggressive and the smaller ones able to escape quick.
Provide more space and don't over crowd and this will works. All colours mix well.
Provide more space and don't over crowd and this will works. All colours mix well.