Some scientists say densely packing fish into cages or nets in natural bodies of water, frequently just offshore, can destroy delicate habitats while the waste generated can elevate nitrogen levels to harmful levels.

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Too much oxygen and the toxic ammonia in waste won't convert to nitrogen gas, which bubbles out.

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Every day four waste treatment plants feed more than 250 million gallons of nitrogen filled wastewater into the bay, a massive expanse of 20, 000 acres of water sitting where Brooklyn and Queens meet at their southernmost point.

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