NANFA-- RE: filterless aquariums, again!

Nicholas J. Zarlinga (
Thu, 1 Feb 2001 14:53:07 -0500

Hey Naturnut, I think that you have found an intesting topic to talk about.
Your filterless aquarium, in my opinion, is what separates two very
different disciplins in aquariology. Your average hobbyist, whether a
native or tropical fish enthusiast, is hammered by everyone they know and
ask to get the biggest, best, most advanced, technologically coolest, most
expensive filters that they can buy for their aquarium. "This is the only
way to keep the numbers and kinds of fish that you want to keep in an
aquarium!" Usually, we get started in this business to keep as many
different varieties of fish together, whatever habitat they are found in.
It is a totally unnatural situation to have so many and such a variety of
fish in such a small amount of water. That is why we need to rely on
"unnatural" or "conventional" filtration. We need to provide a place
(actually a refugium) for organisms to grow in great quantitites to be able
to handle the excessive wastes that the absorbitant numbers of fish per
water volume produce. Fish are the focus in this discipline. Although
some have been doing it all along (here in the US but mostly in Europe),
the vast majority of us have not heard much about this "natural aquarium"
technique until relatively recently. This concept has taken off in the
saltwater part of our hobby with living reef aquariums. Much of the credit
goes to Dr. Walter Adey who is usually credited with algae scrubbers (the
algae filter you mentioned) for making this popular. There were others
involved too. This discipline of aquariology is different in that it is a
much more ecologically minded approach. It is the system which is most
important and the fish are part of the system. An analogy that I often use
is that the sytem is like the human body. All the components of the system
correlate to organs of the body. Although you still are perfectly allowed
to have an unnatural variety of organisms in your tank (unless you are a
purist which is the ultimate right wing of the hobby) but instead of fancy
gadgets and gazactometers to do your filtering and monitoring, you rely on
more diversity of organisms (ie-plants, algae, snails, worms, and other
miscellaneous "critters") to do you food conversions. As in nature, the
more diversity that you have in a system, whether a pond or an aquarium,
the more stable the system is. If these organisms start to decline (or go
extinct) it is only a matter of time before the balance is disrupted and
you have major problems with diseases, (weather patterns) etc. It is so
ironic that this is usually considered the route of the advanced hobbyist
but this is how our hobby started in the mid to late 1800's! No fancy
filters or gazactometers then.

Nick Zarlinga
Aquarium Biologist
Cleveland Metroparks Zoo
216-661-6500 ex 4485

"Fish worship... is it wrong??" (Ray Troll)

On Friday, February 02, 2001 10:58 PM, nanfa
[] wrote:

> Date: Fri, 2 Feb 2001 22:00:08 EST
> From:
> Subject: NANFA-- Filter-less aquariums
> I understand several aquarists have planted tanks with no filtration
> except the plants themselves. The ammonia levels were at nearly zero,
> the nitrite readings the same. Nitrate levels were not as low, but still
> quite low. Some tanks incorporated a sump, and a 10 plastic tank heavily
> planted with floating plants, and the water was returned back to the
> Others were completely self contained, but current is essential. The idea
> that nitritifying bacteria thrives on every part of the tank(glass,
> rocks, gravel, sand, ect) was used. In many instances, a filter was
placed in
> these tanks out of curiousity, and did nothing in the way of lowering
> ammonia, ammonium, nitrites, or nitrates. The filters looked very clean,
> filtering out very little suspended particles. This topic has probably
> allready been addressed, but if anyone has tried a filter-less aquarium,
> please share your experiences. Sorry this is kind of off-topic! Thank
> __Dan

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