High nitrates

[milkman754]

I can’t seem to get my nitrates down. I’m doing regular water changes. I have a refugium loaded with cheato, denitrator in the sump , a nitrate asorbing in the sump as well. I’m feeding less and they won’t go down . What can i do?

 

[Mandelstam]

Tank size? Tank age? Other water parameters? Stocking?

Just to give people a little more to go on and base their advice on.