Pet Forum / Aquaria / Cichlids / June 2004

The filtration accomplishes many things (circulation for heating,
mechanical filtration, biological filtration etc), so there is no clear
answer, it depends on your specific conditions and your fish-load.

If no filtration was your objective, you would have trouble heating it,
so some circulation would be warranted.  You would have to rely on
significant vegetation to consume the solid waste and remove the liquid
wastes from the water, and you would be restricted to a non-reproducing
low fish-load.

Perfect fishroom?... like an acrylic cylinder to house the people (the
fish are between the cylinder and the basement walls).  Inside the
cylinder (which is about 15' in diameter) is a circular staircase from
above and your lounge chair.... or we aren't talking about quite *that* a
large sum of money ;~).

Concrete leeches at a rapid and undesirable rate, so it will need to be
cured and the perimeter sealed (to prevent seepage).  If you provide more
details about size and construction, I'm sure someone will supply advice.
I'd plan on a large sump for biological filtration and perhaps an algae
scrubber.  This would make your life much easier (water changes on a
1000g are not too bad, but gravel vacuuming is a chore, so you might want
to give some extra attention to that (automated gravel vacuum system).
When you get into bigger tanks, the water itself (for changes) starts
becomes an economic consideration, so the algae scrubber becomes very
practical.

At 1000g, you can think along the lines of the pumps and sand filters
used for swimming pools, especially if you are incorporating a waterfall
(you need the extra head pressure for the height).  You weren't thinking
about a waterfall?  You really need to think this through more ;~)