The most important things about keeping SPS are water stability, water flow and light. If you are lacking in any one of these areas, you'll have a tough time with keeping SPS colorful and happy. The latter two are the easy ones.
Keeping Salinity, Phosphates, nitrate, nitrites and ammonia in check are the first step. Then keeping up Calcium, Magnesium and Alkalinity demand is the next. Don't forget about Temperture and pH as well...
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32"x32"x20" Cube-ish tank
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