Refugium setup!!

[xmjxflipx]

Hi guys i just now barely but in some sand and chaeto in my PM refugium, im using daylight flood lamps as a light source.....Ive been trying to find someway to remove nitrates so i was wondering how long do i have to wait before i can see my nitrates lower, Right now im leaning more over on 20ppm this is with a API nitrate test, dont know as far as reliability how accurate it is but its a starting point.