changing a filter....... where to put the old one?

"Media", in this instance just means "stuff", The filter media is, the stuff that does the filtering.
So in the picture, the white pad is designed to do most of the biological filterring. ~it is the biological filter media. The blue thing I suppose does mechanical filtration, and has carbon in it. Supposedly the carbon is for chemical filtration. but as I understand it, is useless after 2 weeks or so.
A lot of bacteria also grow on the blue pad and the carbon, if they are left in.
If you test your water for ammonia shortly after you change your blue filter and see no rise, then cool.
I myself just use it all as bacterial filter media and rinse it out in tank water. I will need to replace the blue part one of these days though because i can see that it will clog. Good to know that I Might get away with it with out trying to preserve its biofilter. I will test the water when i remove it.
 
If you test your water for ammonia shortly after you change your blue filter and see no rise, then cool.


Well me personally. After i put a new one in. My readings are always the same.
 
Well me personally. After i put a new one in. My readings are always the same.

The reason for that is, 90% of your "media" is the white stuff in the pic. When you change the blue "filter pad", the majority of your filtering bacteria is still present.
BTW I have one of those Blue filter pads in my HOB and havent had to change it in about 3 months! doesent clogg, water runs through as easily as the day I got it. Go Figure:huh:
 
Medium means, "An intervening substance through which something else is transmitted or carried on." The plural of Medium is, "media". Medium also means, "A filtering substance or material."

This includes everything inside of the filter.

:thud: 'xactly what I meant. Now why didn't I think of looking up a definition?
 
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