Ich/Finrot filter related question.

[Jason the Lost]

My question is this. I introduced some Black Phantom Tetras to my tank and like every fish I've purchased from PetsMart, its had issues. Live and learn...I won't be buying livestock from there in the future.
These fish seemed perfectly fine and when I introduced them into my main tank (20gal) the next morning 3 of them and my swordtail had the ich. This started roughly around last Thursday. I immediatly started increasing the temp and the tank has been at 86-87 degrees since Friday evening. The Ich has disappeared completely from the swordtail but I've lost two tetras. Of the 4 surviving tetras 2 look perfectly fine, one looks like a pretzel hes so ich'd out, poor little guy...and the other seems like hes clearing up.
The problem...one of the dead and the one who is clearing up are/were suffering from some pretty extreme fin rot...the dead one lost almost his entire tail and the living on has about 1/16" of dorsal left. I started treating the tank with melafix last night but I'm wondering about the filtration. I have an 8 day old Penguin Power Filter 150 running ( I chanegd the filter before my cycle was done but the stock filter was terrible that came with the top fin starter kit...the intake was way too high and I couldn't find any extensions...so I treated with bio spira and things seemed to be falling in place till the ich))...is the charcoal in the filter detrimental to the meds? Should I take it out? Should I put somthing else in?
I'm nearing the end of my nitrogen cycle so I'd hate to set things back...but I don't need any more dead fish either.

[Meredith]

I would take out the carbon, but leave the floss behind if you can.

[Jason the Lost]

how do I do that? cut it out?

[rich311k]

If the filter pad has been in more than a week the carbon is pretty much spent anyway. You may be able to just let it be.