View Full Version : carbon for magnum HOT canister filter

01-06-2015, 04:49 PM
What are the pros and cons for using activated carbon in the canister filter? There are different types on the market. Which is best for aquariums? Can you recommend a brand and a source? I have used activated carbon for a long time but in reading about it there are some experts who say it isn't needed. Thanks for any information you could provide!

01-06-2015, 07:14 PM
The Good:
Activated carbon will quickly remove organic and inorganic compounds from your water. This is great when you eliminate some unwanted compound from your tank.
I don't like to overcrowd fish, but sometimes it's unavoidable. In those circumstances, I've used it in tanks where I know I need overcrowd a few hundred plant eating juvenile cichlids when daily water changes aren't enough.
The Bad:
Removes organic and inorganic compounds quickly, but, because it's so active, it doesn't remain active for very long (only a few days).
After it becomes saturated, it can start leeching some of those compounds back into the tank if the carbon isn't changed.
I keep planted aquariums so I would never use activated carbon as it would absorb many of the compounds that my plants need.
It takes up valuable filter space in my filters that I could use for mechanical and biological filtration.
The Good and Bad:
If you're medicating a tank for any reason, activated carbon will remove the medication.

I typically use Marineland's Black Diamond premium activated carbon. It seems to work well.

That's all I can think of so far.


01-06-2015, 09:54 PM
I use the same brand in my HOT magnums. I don't think the brand is important, though. You just need a particle size large enough not to go through the screen and get into the impeller well. I have also replaced carbon with ceramic (rings or Matrix) and dolomite or crushed coral for Tang. tanks. Plain gravel works too.

01-12-2015, 07:29 PM
Brands do matter . Many actually leach phosphate into the system