It is a pretty good deal. People like them (including myself) because they are a nice clean looking all-in-one system. That being said, they are not without problems. There is really no good place for a skimmer and the sponges, bioballs and ceramic rings it comes with for the filtration compartments are not exactly ideal (or reccommeded) for
SW tanks. When i set up mine, I replaced all of the media it came with for the back with
LR rubble and had to add another
PH to increase the flow. Otherwise, I am very happy with it. As for size, it is up to you. the 12gal has more intense lighting so it may be better for corals is you plan to go with a reef in the future. As bearfan stated, if this is your first
SW tank it may not be the best choice due to it's size, but it can be done. Good luck...Lando
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