How much Carbon and GFO per gallon?

[MstgKillr]

How much Carbon and GFO does everyone use per gallon and how often do you change it?

[Froggy]

Ok, I do not use GFO but this is my understanding.

The reccomended dosage is 1 TBs per 10 gallons. If you have never used GFO before it is a good idea to start much lower, maybe 25 % of that and build up. You can easily shock an existing tank that has not been exposed to GFO before.

Depending on the phosphate level in the tank, you change it based on testing etc. With very high phosphate levels, the GFO can get exhausted quickly and need changing until the levels stabalize at a low level.

As far as carbon, 1 cup per 50 gallons is a pretty fair rate. I try to change my carbon monthly.

[mattT5]

start with 1tbs per 20 then move it up to 1tbs per10 gal when you change it

[Conky]

My interpretation of this recent article caused me to increase the quantity that I'm using...about 1 gm per gallon currently, changed monthly.

http://www.advancedaquarist.com/2008/2/aafeature1/view?searchterm=carbon

I follow mfg. instructions for GFO and haven't had any issues yet.