Hello monsterfishkeepers, I have a 55 gallon tank. I have 3 gold severums, 1 green severum, 1 blue acara and 1 convict. The green is the biggest, then the acara then the golds and the convict is the smallest. My questions are....: when they are all fully grown is this to much fish for the tank and will one of them in particular (or more) kill the others?? Can I add more fish?