Recommended or a reef---level of 2 or less.
For a FOWLR tank or fish-only: less than 30.
For many inverts, the survival limit: under 40.
Fish survival limit---maybe 100, but it's not going to be happy.
Some things actually use up nitrate: clams, for instance, reduce nitrate, but have many other high-end life requirements, so don't dump some poor clam into a fish-only.
Some corals like elegance also appear to require a little, so zero is not good for them.
Your live rock is a big consumer. The way one pair of human lungs, completely flattened, would cover a football field (so I've heard: never tried it)---one live rock, similarly flattened, should have a lot of pores, passages, holes, gnarliness. It should not be, say, a chunk of smooth marble. Pores, holes and passages to let in a lot of water to be processed.
Where does nitrate come from? Nutrients. Food. Biological process you met when you cycled your tank, or would have, had you done it the 'old' way, and simply added fish food.
How to lower nitrate?
Feed only what fish consume...eliminate waste.
Ditch (little at a time!) bioballs, filter pads, sponges, wet-drys, canisters, filters, and any other arrangement that lets waste pile up in a system for bacteria to work on.
To deal with waste, have enough live rock, do your water changes, and don't have too many fish for your tank to handle well. Live rock and sandbed, aided by worms, crabs and snails that break down food particles, can break nitrate down and convert it to nitrogen gas, which floats up to the surface as bubbles, and goes away. This is not a case of something FOR nothing, but something converting TO nothing. Buh-bye, nitrate!
For a FOWLR tank or fish-only: less than 30.
For many inverts, the survival limit: under 40.
Fish survival limit---maybe 100, but it's not going to be happy.
Some things actually use up nitrate: clams, for instance, reduce nitrate, but have many other high-end life requirements, so don't dump some poor clam into a fish-only.
Some corals like elegance also appear to require a little, so zero is not good for them.
Your live rock is a big consumer. The way one pair of human lungs, completely flattened, would cover a football field (so I've heard: never tried it)---one live rock, similarly flattened, should have a lot of pores, passages, holes, gnarliness. It should not be, say, a chunk of smooth marble. Pores, holes and passages to let in a lot of water to be processed.
Where does nitrate come from? Nutrients. Food. Biological process you met when you cycled your tank, or would have, had you done it the 'old' way, and simply added fish food.
How to lower nitrate?
Feed only what fish consume...eliminate waste.
Ditch (little at a time!) bioballs, filter pads, sponges, wet-drys, canisters, filters, and any other arrangement that lets waste pile up in a system for bacteria to work on.
To deal with waste, have enough live rock, do your water changes, and don't have too many fish for your tank to handle well. Live rock and sandbed, aided by worms, crabs and snails that break down food particles, can break nitrate down and convert it to nitrogen gas, which floats up to the surface as bubbles, and goes away. This is not a case of something FOR nothing, but something converting TO nothing. Buh-bye, nitrate!
