Common Charcoal Options

[ttsen]

guys, i need to know.

can i use the common charcoal to eliminate smell and toxins? i've experimented for 1 wk now with 1 large pc about 6" long in my green water tank. so far it takes away the smell unless you stick you nose a few inches away from the water surface.

will there be any adverse problems? does common charcoal act like activated carbon or not so good? i know ac will 'ROD' in about 2 months or so. will common charcocal also 'ROD'?

i know ac absorbs heavy metals in the water, can common charcoal do the same? can carcoal 'take away' nitrate and nitrite? or that can only be done by water change.

thank you.