How Long does GFO & Carbon last?

[YoungReefer_18]

I Just installed Dual Reactor from BRS on Aug 21 should I change it every two week or once a Month???

 

[bubbasguppies]

Test your Phosphates and replace as needed when your values start going up. Carbon you could do monthly.

 

[YoungReefer_18]

Test your Phosphates and replace as needed when your values start going up. Carbon you could do monthly.

Thank You I'm test my phosphate levels