Nitrate can be reduced though the production side by not feeding excessively and siphoning out waste.
To get rid of nitrate that is already produced is tougher. A little escapes into the air as nitrogen gas as stated before. And frequent water changes will maintain a low level. But to reduce down to zero you must have some sort or nitrate reducing system. That usually consists of some sort of system for culturing anaerobic bacteria. Anaerobic bacteria are bacteria that cannot live in the presence of free oxygen or hydroxide radicals (OH) Large pourous liverock can sometime hold anaerobes in its core and therefore some reefers can have success with just liverock. DSB's of greater than 3 inches can result in an anaerobic layer on the bottom. And then there are reactors like coils and sulpher beads that pump water through them slowly enough to prevent oxygenation.
The other best best is a refugium with macroalge that consumes the nitrates.
Thats about your only options.
Mike
To get rid of nitrate that is already produced is tougher. A little escapes into the air as nitrogen gas as stated before. And frequent water changes will maintain a low level. But to reduce down to zero you must have some sort or nitrate reducing system. That usually consists of some sort of system for culturing anaerobic bacteria. Anaerobic bacteria are bacteria that cannot live in the presence of free oxygen or hydroxide radicals (OH) Large pourous liverock can sometime hold anaerobes in its core and therefore some reefers can have success with just liverock. DSB's of greater than 3 inches can result in an anaerobic layer on the bottom. And then there are reactors like coils and sulpher beads that pump water through them slowly enough to prevent oxygenation.
The other best best is a refugium with macroalge that consumes the nitrates.
Thats about your only options.
Mike
