I am thinking about upgrading my tank. I currently a 40g which is over stocked and a 50g which houses my (2) Myleus Micans which are around 9-10in each. At the moment I have them divided because their both males and don't really get along and like to fight and bit each others fins. So I want to upgrade my 40g to a 120, 125 or maybe 180 gallon thats if I can find the 180 for an awesome price, which I really haven't had any luck in finding. The whole reason for this upgrade is so I can pretty much give both my Micans enough tank room into which they can swim in and not have them be so aggressive towards each other. Also when I do get the new tank I want to add in (7) 2" Myleus sp. which are are unknown at the moment and (4) 4" Myleus Fasciatus which are in my 40g. the rest of my fish that are in my 40g will be transfered into the 50g. So which size tank should I get a 120 or 125 gallon? or should I wait till I find a 180 that is selling at a good price in my area?