? about carbon filters and liquid plant fert

Ok, so then maybe I shouldnt bother with the fertilizer? As for the carbon I just pretty much put it in there because I dont need the ammonia remover bag that usually goes in its place in an aquaclear filter and have never tried it without the carbon. Waters always crystal clear and odorless so I guess it serves its purpose although I rarely ever go over a week before water changes. Thanks folks.
 
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