[Ask?] ]Filter Media

[arkana1]

dear all:
what filter media should be placed first in filtration flow? i'll try to combine all filter type, mechanic, biological & chemical in one unit

the flow process show like this:

dirty water - mechanic filter - chemical filter - biological filter - clean water

or

dirty water - biological filter - chemical filter - mechanic filter - clean water

any ideas?

some canister filter placed the sponge filtrat at the end of outlet

[neilanh]

My preference is your first solution above, with the mechanical filtration first.

[arkana1]

thanks for your opinion.

do you think the bio filter still work effectively if the water is 'too clean'?

[missileman]

The water will not be too clean because the other filters will not remove any appreciable amounts of amonia or nitrite.That is what the Bio-filter is for.
Secondly you do not want garbage in your biological filter, it will just plug it up and ruin its effectiveness.
Bio-filter always goes last, period.
Read up on cycling an aquarium.
The bio-filter is where beneficial bacteria live (but not the only place)

[arkana1]

ok, i understood..

just my thought, bio-filters work by using some bacterial organisms and the filter media (bio balls or ceramic rings) maintain them there.
so, no matter how clean the water is, the bacterias will keep on living inside the filter. right?

[missileman]

Exactly.
The Bacteria feed on amonia and nitrite which is not removed by the other filter media. The end product is nitrate wich is safe for most fish up to 40ppm and nitrate is mostly removed through regular partial water changes (PWCs)

[arkana1]

i read some articles, they said that bacteria consume oxygen. so this the reason behind wet/dry trickle filter is the most effective bio filter method. cause the water flow on the open system makes a good oxygen exchanged.

my question is: how to enrich the water with oxygen in the closed system like canister filter? does the bacteria get enough oxygen's supplies inside the canister?

[missileman]

I don't know how much oxygen exchange can occur on a closed system.
To get better oxygen levels in the water column you can add a power head to agitate the surface or an airstone which will also agitate the surface which will aid in oxygen exchange as well as help oxygenated water to circulate to the bottom of your tank where some fish like to hang out.
I run a single airstone on all of my smaller tanks, 2 on my 46 gal. and an air curtain about 5" long on my 75 gal.
PS: keep in mind that the filter is not the only place the bacteria live and bio-filtration takes place throughout your tank.
The bacteria also lives in your substrate, on your glass and on ornaments in your tank.

[arkana1]

i see.
thanks for you info..

[arkana1]

Originally Posted by missileman

I don't know how much oxygen exchange can occur on a closed system....

does anyone know?

closed system such as canister filter
open system such as wet/dry trickle, sump filter

[Telek]

Actually it's quite the opposite - the whole point of the closed bio-ball system is to remove nitrates by providing a very low oxygen environment. In that environment denitrifying bacteria becomes anerobic and breaks down the nitrate entirely to nitrogen and oxygen. The nitrogen is released harmlessly and the oxygen is consumed by the bacteria.

[arkana1]

i read this article:
Simple Nitrogen Cycle | Biofilter Media & The Nitrification Process
..and hopefully not mistaken.

it says: bio filter is nitrification process. two bacterias call Nitrosomonas sp (turn ammonia into nitrite) & Nitrobacter (turn nitrite into nitrate). they both need oxygen (aerobic ones).

[gzeiger]

You're right, arkana. Some people have used a deep sand bed to create the effect Telek is describing, but a canister filter will never be an anaerobic zone. Saying that there is no gas exchange in the canister itself is not at all the same as saying there is no oxygen in the filter. There is plenty of oxygen already in the tank, or your fish would be dead. Oxygen is constantly dissolving at the surface of the aquarium, and it's taken into the filter along with the water in which it is dissolved.

I suspect the oxygen argument is just a marketing gimmick on the part of the wet/dry manufacturers. What they're telling you isn't strictly untrue, but if fish can live in your water then so can the bacteria.

Most people just remove the nitrate through water changes since fish can tolerate a relatively high concentration of nitrate while ammonia and nitrite need to be pretty much zero. The anaerobic filter concept is also dangerous because if disturbed it will put some very poisonous chemicals into the water.

[arkana1]

Originally Posted by gzeiger

...Saying that there is no gas exchange in the canister itself is not at all the same as saying there is no oxygen in the filter. There is plenty of oxygen already in the tank, or your fish would be dead. Oxygen is constantly dissolving at the surface of the aquarium, and it's taken into the filter along with the water in which it is dissolved....

thanks...your explanation is kind of logic. i don't have to modify my canister then...