Re: Trickle Filtration vs Canister Filtration

From: Zon Hisham Bin Zainal Abidin <zon at mad_scientist.com>
> Are these true?
> 1)Trickle filtration method will cause quick oxidation of iron.
> 2)Use alot of CO2
> 3)For planted tank, canister filtration is better than trickle
> filtration.
> I have referred to George writeup on his SST where he used trickle
> filtration. And there was no complaint about quick oxidation of iron.
> But hoping to get a general opinion from the public.

I can't answer #1.  I have never heard of such a thing though.  I have read
where nitrifying bacteria do consume some amount of iron, but I suspect it
is not much as these same bacteria thrive in non-planted tanks with no iron
supplementation.  A trickle filter will develop no more nitrifying bacteria
than a canister.  The amount of bacteria is limited strictly by how much
they have to eat.  If #1 refers to the additional oxygenation of the water
as it passes through the trickle filter then I would say that #1 is false. 
A heavily planted tank is going to be in an oxygen saturated state during
the day anyway, regardless the filtration method used.

#2 has been covered extensively by George.  I'll refer you to his article
on CO2 loss and trickle filters.  It can be found on the Krib.  He found no
additional CO2 loss with the use of a trickle filter.  The media chamber
may initially degas some CO2 but the atmospheric CO2 in the media chamber
will eventually equilize with the water.

#3 This is personal preference.  Both do the job of providing biological
and mechanical filtration.  I prefer trickle filters due to their ease of
maintenance and flexibility (due to the sump, pump and plumbing).  However,
canister filters are much cheaper.  I do feel a trickle filter is overkill
(biologically speaking) on a heavily planted aquarium.  I have one tank
(58g) that currently has a single powerhead (and sponge) for circulation
and mechanical filtration only.  Nitrate levels are around 10ppm.