"Dick" wrote in message
...
On Sat, 23 Apr 2005 16:16:45 -0400, "NetMax"
wrote:

"m" wrote in message
. ..
My friend is setting up a 5 gallon tank for some killies and he's not
planning on using any substrate.
My question is this: is substrate important other than for
decoration?

Depends on the situation. Very small fry will hide between the pieces
of
larger diameter gravel (though I don't know if that would be the case
with Killies). The gravel also provides a significant amount of
surface
area for good bacteria. While not as efficient or as important as the
bacteria in your filter, the gravel doesn't have the same risks as a
filter (changes in flow due to clogging, power failures, sterilization
due to improper cleaning etc), so it provides a small buffering effect.
Gravel is not essential, and also has some disadvantages. I wouldn't
be
concerned about not using any substrate.

Will he be able to cycle his tank without it?

Yes, I don't see why not. Install a filter using well used filter
media
from an established tank and you are essentially cycled.

-m

Netmax,

I think you just confirmed what I have been suspecting. My hospital
tank is bare bottomed. It is the only tank I have with cloudy water.
It has one Whisper Jr. so when I clean the media, the main bacteria
refuge is purged. I have been thinking it is the lack of gravel to
hold the bacteria.

I have 2 other 10 gallon tanks with Whisper Jr.s, what would you think
if I cleaned one of those other filters, run it for a few days, then
put it in to the hospital tank filter and then clean the dirty
hospital filter media and put into the tank that has gravel.

Any thoughts?

dick

Sounds ok if your hospital tank is being used for isolation, quarantine
etc. If is for disease management, I wouldn't like sharing the sponges
back & forth too much. I'm not Elaine ;~) but I like her idea of sponge
filters for small tanks like this.
--
www.NetMax.tk