Filter Medium

[This Old Spouse]

I have 3 different setups going, but all use the replaceable carbon cartridges (Bio-Bags). Thanks to this forum I've already learned that I should never just replace the filters with new ones but to rinse them out in tank water. (I received all my tanks and accessories free so I don't have any documentation for any of it.)

However, the more I read on this forum, the more it appears I shouldn't be using the Bio-Bags at all but most likely sponges or ceramic rings or both? One of my filters has a pair of media baskets that I now have a bio-bag stuffed in both.

I really would like to get my setup as good as I can for my fish. I already made the mistake of putting gravel and pebbles in my 55 gallon, and it's most likely going to stay that way until I buy the next house and move! But if I could get the filter setup correct, I'll sleep much better at night.

I'm sure after another year of reading the posts I'll have it all down pat.

 

[Uriel]

Filter carbon isn't useless it's just that it's chemical filtration.

3 types of filtration

Mechanical = Filter floss, certain gravel types and sponge. Removes floating particles from the water like bits of plants fish poo ect.

Biological = Sponges, bio balls, ceramic rings. Act as surface area for the nitrify bacteria to build up on. converting Ammonia -> Nitrite -> Nitrate

Chemical = Carbon. Used to remove chemicals from water. Generally only needed if removing medicine treatments or if you have a lot of bog wood and want to remove tannins.

Personally i believe biological filtration is most important for fish but as most biogical and mechanical filtration works for both it's not worth getting overly hung up on it. If you already have some form of sponge or similar filtration i would add ceramic rings or similar to you baskets.

 

[waterdrop]

When we write that most of us don't use carbon or other "chemical media" on a regular basis it can sometimes sound to a beginner like it's somehow really bad that they set up their new filter with the media it came with and now have the wrong stuff in there.

It's not really like that. Carbon is basically only a chemical media for 3 days. After that it has "adsorbed" (molecular charge attraction) all the charged particles it's going to adsorb (it is indescrimanant in the things it collects, substracting both bad and good things from the water) and is (if one is using it strictly as a chemical media as is usually advisable) ready to be tossed in the trash. BUT, carbon (aka activated charcoal) is not a terrible biomedia as a secondary function it can serve. It has generally high surface area and lots of bacteria will populate it, if perhaps somewhat more slowly than some other media types due to all the chemicals it as adsorbed!

The reason it's not one of the top choices, I feel, for a biomedia is simply because it is so "crumbly." It gradually crumbles and tiny bits of it get carried out with water changes even though they are too small for us to see (dust, so to speak.) Each of those tiny bits is bound to have some of our precious autotrophic bacteria riding along, since they are even smaller than the "carbon dust." As such, it's just not quite as effective and certainly not as long term a biomedia as sponge or ceramics or dish scrubbies, which are among the top biomedia types. But all this sort of problem evolves very slowly and this is to your advantage, as you have an even more important concern in that you want your nice big set of bacterial colonies to never be depleted too much by any sudden change you make. This gives you lots of time (months and months) to be quite creative about any sort of media transition you want to make! You can study up, shop and devise to your hearts content and that carbon will be still basically taking care of business anchoring your two species of autotroph.

~~waterdrop~~