Goldfish with Possible Columnaris - Help with Maracyn
 

Why they can't make the instructions a little clearer is beyond me. Anyways, as the subject states, I believe my baby fantail goldfish may have columnaris. She has the typical fuzzy stuff going on and has been hiding in a corner, refusing to eat or pretty much move. I'm going to treat with Maracyn unless advised otherwise but I just need a little help clarifying the instructions.

They are as reads: "Add the contents of 1 packet per 10 gallons of water and repeat every 24 hours for 5 days." Does this mean I do a 100% water change every day on a 10g tank before adding in the new packet? Otherwise, the instructions seem to imply that I put in a new packet every day along with the previous day's existing packet in the water? Am I making sense? (I'm not making sense to myself, haha). I'm just worried that if I put in a new packet every day without changing the water, the medication will build up.

Also, I am using a Penguin Bio-Wheel filter so the carbon is encased in the mechanical floss. Do I remove the entire carbon/floss cartridge then before adding in the medication? Will the filter function with just the Bio-Wheel and no cartridge?

Thanks in advance for all advice. It is much appreciated. :)