I wouldnt put a seaclone on my tank.....and its a 29 gallon. If you plan on keeping corals.....or sps in particular.....I wouldnt put the seaclone on a 20 gallon. Im not a fan of the design but in all honesty.....and this applies to every part of life......You get what you pay for. I found it out the hard way. I bought a coralife super skimmer.....and yeah it skimmed great......but it was brittle.....and it overflowed at least once a week. It was just a head ache and almost made me change my mind about saltwater. I did my research.....found that what I have now....cant overflow and I switched. After I went skimmerless for two months....I made the switch to my Aqua C. and I love it. If you put a body kit on a Civic to make it look nicer.... it will look nicer.......but it will still perform like a civic.........if you buy an audi........it will perform like an audi.