Carbon options?

[bluesox68]

So can someone please tell me how long carbon is good for "roughly" and does it last longer and lets say more effictive in a reactor then in a bag filter with high flow? My tank is a 40 display with a 20 sunp. Thanks

[windcoast reefs]

I find it lasts between 2 weeks to 2 months depending on the quality of the carbon, level of nutrients, clarity of the water. All sorts of things effect the length of time it lasts. I would probably start by replacing it every 2 weeks for a month, then go to changing it once a month. That's what I did at least.