I used a rubbermaid bin to transport water once for one of my big tanks. A lot of Rubbermaids are made with a softer, pliable plastic, which can buckle, or bend under pressure i.e. putting water in it. If I am mistaken and you have one made of hard plastic, you have another problem all together - it could crack...very easily. and believe me, you do not want 20 gallons of water on your floor. Plastic is EXTREMELY porous and can have chemicals in the plastic that you can't smell or see, which could leech chemicals into the water you put in there, causing a toxic environment for your fishie friends. This could also cause buildup of chemicals you use in your tank further down the road....also problematic. Ultimately, it will give you less control of your parameters.superwaterguy52;81223 said:Ok, I guess I was getting a little ahead of myself, because I have no clue as to what some of you guys are talking about. First of all, what did you mean by "buckle", DrBatty? And what are baffles? And what are bulkheads and what is a DIY system? I guess what I need to know is, what are all the things that you need in a sump, and what do they do?