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I seem to be getting conflicting info on whether or not I should run carbon in my canister filter all the time or only maybe for a few days in a month, as I am new to marines/inverts I would appreciate your advice.

I thought that carbon was a must have! I have a full canister of it in my system. Am I hurting something?

I believe you are in danger of removing (leaching) a variety of necessary minerals from your system long after the carbon has become saturated with organics. IMHO a good activated carbon is best used @1 cup per 100 US gallons for three days A MONTH!

Carbon should only be used for three months and then replaced, I believe that most packaging state this. This is because after this time the carbon can start to leach back what it has taken out.

Some believe in continuous use of carbon i.e. replacing the carbon every three month, some believe in only brief use i.e. for one or two weeks every few months and some believe in quick use i.e. two or three days a month.

I am sure that there are compelling reasons put forward for all the applications of carbon.

Personally I replace my Carbon every three months. I use HR Carbon pellets and rinse it in RO water before use. At the very least I have found that without the carbon the water gets a yellowish tint over time.

It is rumoured to "strip" the water of some beneficial elements. But nothing is concrete on that front. It is also rumoured to be an indirect contributor to HLLE disease if used constantly ... which is definitely worth considering if you have tangs or angels, or large fish.
Personally, I would recommend NOT using constantly, but rather one day a week, for 24hrs, or perhaps for 3 or 4 days every month, to polish up the water and remove any slight chemical build-up.

In my opinion, it should not be used continuously. Nearly all the experienced marine keepers I know have advised me of this.

Activated carbon tends to remove the beneficial minerals from your water as well. It can also become "saturated", and then leach all the "baddies" back into the water. Lastly, detritus tends to get caught in the carbon (over time), where it then decomposes, releasing harmful substances into the water.

I would recommend that you use carbon sparingly, say two to three days per week (max.), and then rinse it clean before re-using it. Also, discard it after two or three weeks.