re: No Filter Planted Tank

---------- Forwarded message ----------
Date: Wed, 01 Jan 1997 20:28:52 -0500
To: Aquatic-Plants at actwin_com
From: Neil Frank <nfrank at mindspring_com>
Subject: Re: No Filter Planted Tank

David Webb in response to R. Williams' question about tank's without filters
>I have a 5.5g zero forced water movement tank at my office.  This tank has two
>fish in it (small platies) and a few snails.  I feed twice a week with flake
>The platies do not seem to have a problem with low oxygen levels in the water,
>but I keep the water shallow.  The deepest it has been is about 3", and it's
>currently 2" deep.  

Dave: you should not have any problem even if the tank was filled to the 8
inch level. I keep all types of aquarium ranging from the "high tech" to
many without filters or heaters. The latter are mostly 10 gallon tanks in
which I raise Cryptocoryne with livebearers. The conditions for the fish may
not be optimal, but is more than sufficient for them to thrive. The number
of fish vary; in one tank with Limia perugai, I counted 7 fish. Livebearers
and other fish will eventually determine the appropriate number that their
container can support.  I have also kept Tanganyikan cichlids in 15-20
gallon tanks outfitted with a single triangular sponge filter. Too often to
count, I have found the airline tubing clogged and the filter was not
working. This did not affect the fish and prevent them from breeding and
thriving. These tanks would have java fern, java moss and attached algae on
Even without plants, an unfiltered, unaerated tank can support fish. I once
kept a firemouth cichlid in a 1 gallon jar - no filter, no aeration. The
fish started out as a fry and it lived there for over a year, eventually
growing to a couple of inches. I previously did the same with a Geophagus
steindachneri. Both times, the jar was on a shelf in front of a window and
had the single fish to supply ammonia to keep the water green (i.e.
suspended algae). Other people have used goldfish for this same purpose.
Using airline tubing, I siphoned the water on a weekly basis to feed a
daphnia culture. I seem to remember that the fish would be more listless and
hang around the water surface after few sunless days, but this did not cause
any long-term distress. The suspended photsynthesizing algae normally
provided sufficient O2, just like it does in a catfish pond. If I was more
careful, I am convinced that I could have kept the fish alive for years. In
both cases, I carelessly let the airline tubing drop too far into the jar,
forgot about it and returned later to find a crispy critter. 

Who expects to participate on this list more often in 1997