Raising Japanese fugu puffer fish to maturity, for instance, normally takes five years, but it only requires two and a half years with deep-sea water. The Japanese therefore take advantage of deep-sea water's cleanliness and low temperature to hatch fish, or first raise the larvae of high-value seafood like abalone and lobster in deep-sea water, and several months later transfer them into ordinary seawater once they've grown strong.
以日本河豚為例，原來需要 5 年，養在深層海水中只要 2 年半就可長成；日本也利用深層海水乾淨、低溫的特質來孵育魚種幼苗，或者將高經濟價值魚種如鮑魚、龍蝦的幼苗先養在深層海水中，幾個月「頭好壯壯」後再用一般海水飼養，稱之為「過水」。