mechanical and biological filtration? need help.

Research the nitrogen cycle, understand this will help in maintaining your aquarium.

In a nutshell, waste from fish, uneaten food and dead plants breaks down into ammonia. There are colonies of bacteria that convert the ammonia into nitrites and the nitrites into nitrates.

Biological filteration is that which has media designed to house these colonies of bacteria. The filters will remove the ammonia and nitrites from the water. You will then have to keep the nitrate levels low by doing regular partical water changes.

The mechanicla media will trap the debries in your aquarium. This will give your aquarium water a cleaner look. If you frequently clean the mechanical media and remove the fish waste, uneaten food or dead plant material, you will lighten the biological load. Lightening the biological load will have and end result of lower nitrates, but water changes will still be necessary to keep the nitrate level acceptable.

yup! biological filtration keeps your water free of the stuff that can kill your fish, like ammonia and nitrites.

mechanical keeps your water looking clean. ideally, you should have both

Good mech filtration = clear water
Good bio filtration = healthy water for fish.

Either lacking = ugly tank.

daryllee123;2060529; said:

does that mean that i got to have two filters? one bio and one mech? or are there filters that cater to both?

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The biggest percentage of aquarium filters are designed for both. Some fitler designs are better designed for one or the other though. The main thing you want is for the water to pass through mechanical filtration first, usually a sponge, foam pad or filter floss. By doing this the bio media doesn't get as dirty keeping surfaces clear for bacteria growth.

Myself on my bigger tanks I run multiple filters. I use AC110 HOB(hang on back) filters for mechanical, these get cleaned on a weekly basis. I also use a cannister filter which is mainly setup for bio, these only get cleaned every other month.

daryllee123;2060683;2060683 said:

oh i see. thanks for your help.
what kind of filtration should i get for my 120g that i will be getting soon? its a 4'x2'x2'.

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That will depend on what you intend to stock in it.

WyldFya;2060878; said:

That will depend on what you intend to stock in it.

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daryllee123;2057605; said:

my tank is a 120g with a spotted gar, endli and ornate.

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Do you have the fish already? Because if there is no filter on your tank everything is going to die. And then the world will implode.


You don't have to have a special filter for each. Most will come with bio-media, which has lots of surface area for bacteria, and mechanical media, such as sponges or fiber-type stuff. Put both in and you are good to go. (just make sure the tank is cycled first, or you will run into that everything dying and the world implosion issue)