5teady_2012
Here to help
if you read the description it says..
Chemical filtration: Special activated carbon to eliminate water clouding and unpleasant odours
EasyCrystal® Filters are extremely easy to clean: Replace the filter cartridge every 4 weeks. No need to rinse the filter medium, no more wet hands!
i will say, after doing a treatment you should ALWAYS replace the carbon sac with a new one.
My filter has 2 diffrent filters, 1 of them is a white and green, combined and inside of them is the carbon bits. this replace every month it says
The other is the biofoam filter, this is the one i replace rarely it says.
The point im getting at is, which filter to remove, and it seems its the white and green one as this has the carbon in it,, but i have got some of these cartridges without the carbon in..
One box has the carbon bits in them, and the other box of filters has the cartridges without the carbon
So i guess that the ones without the carbon i can put in and still treat the tank right?..
Thanks