HOB Filter and Charcoal

[Maltimomma]

Ok, so over and over I've read where you don't need charcoal in your HOB filter except to remove meds. True or false? I'm using aqua tech with the filter pads you buy at WalMart and of course they have charcoal in them. I'd like to know what to use in place of these pads? If you take out the pads, what keeps the crap, etc from flowing back into the tank?

 

[librarygirl]

You could use just some plain filter padding and cut it to fit your filter, or/and filter sponges like these:

Amazon.com: TOM Aquarium Poly-fiber Filter Pad 3 pack fits #1350, #1351, #1315 & #1316: Pet Supplies
http://www.amazon.com/AquaClear-Foam-Filter-Insert-Sponge/dp/tech-data/B00429UWKI

I've read different things about carbon. Some say you shouldn't leave it in there because after a while it can leech stuff back into the tank. Others say it just becomes inert and isn't harmful at all. Whatever you do just be careful about replacing them all at once or too often as it can throw your tank into a mini-cycle. In general filter media doesn't need to be replaced until it's literally falling part.