Ive had my nitrate removal sponge in for 6 weeks now, juwel recomend you change it for another nitrate removal sponge but would there be any harm in me keeping the sponge in and would it act like one of the blue sponges, obvisouly i understand it would no longer be acting as a nitrate sponge anymore, or do you think i should just remove the nitrate and carbon filter and replace it with 1 large course blue sponge? Ta







