how do i removed medication from water?

what if i do a massive water change? the reason im asking is because the filter is one of those internal whisper filters... and unless i remove all the media, theres no space to add anything.
 
Do a couple of 50% water changes over the next few days, then just keep doing water changes every second day for a wek or so and it will eventualy be taken all out. If you have no room in your filter , just put carbon in an old stocking and leave it in the tank for a couple of weeks, not pretty ,but effective.
 
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