beblondie;1933784; said:Just so you know either you'll be upgrading again soon or you need to get rid of some of the fish you have.A sinlge adult oscar needs a minimum of 75 gallon tank they usually reach 12'' are are known as dirty fish they are messy eaters and tend to rpoduce an incredibble amonut of waste and slimecoat.The pleco if its a common pleco reaches over a foot adult size.and the pacu can easily reach 2 feet in length.So youy are looking at a tank in the 150 gallon range-Anne