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Our aquarium does. We pump seawater from the Otago Harbour (fortunately it's not polluted!!!) into large reserviours which is then used by both the aquarium and the research lab. The water is filtered through sand filters to remove any silt etc (the Harbour is very shallow and gets pretty stirred up if it's windy!) . We use large venturi pumps and have several backup pumps including one run by a diesel genny.
Down here in Glaveston the National Marine Fisheries takes water straight from the ocean for there sea turtle farm they have a pipe that runs out a ways under the sand. The sand filters the water naturally.
We take water out through well screens into two header tanks or around 40000 litres each. This is then pumped through two large filters which have to remove iron (clever council...) and is then pumped into tanks and then over flows back out. We have to treat the water from some of the creatures which come from areas not as clean as the UK by using caustic soda