How often should I replace carbon?

[ReefJCB]

Just recently got a carbon reactor for my 125g. I purchased a BRS reactor with their premium Rox 0.8 carbon.

Directions call for 1 TBSP per 10 gal, my two questions for that are:

1: How often should I replace the carbon?
2: MY reactor has room for quite a bit more carbon. Would adding more mean I need to replace less frequently or be beneficial in anyway?

 

[SPR1968]

I would just follow the dosing instructions and personally I change it every 4 weeks

 

[derekgoude]

I don't measure how much I use, I just dump some in there. The GFO I do measure and write it down.

If your water is pretty yellow to start, might want to run the carbon for 1 week then replace. After that replace once a month or so is what I do. Others will say run it for one week and only once a month. I haven't seen any research about replacement intervals, but I also don't look. Red Sea recommends replacing every 1.5-2 months for their product. I bought 20 lbs of carbon off eBay and I'm not exactly frugal with it's use. Replacing every 2 months makes the reactor a bit of detritus trap for me.

 

[Snoopy 67]

What you DON"T want is carbon moving around inside the unit.
This will produce "fines" & this has been linked to HLLLE .
That's why we rinse carbon in the 1st place.