[header] How to set up a fish tank for plecostomus catfish [title] Buy the right size tank. [step] Pleco catfish can be large, so it's important to have a tank big enough for their size and how many plecos you want to have. Plecos can be up to 15-24 inches long when they're fully grown. 
[substeps] Your tank should ratio should be 1 gallon of water for one inch of fish. Pleco catfish live for 20-30 years, so it will take them awhile to reach their full grown size.