OFL wrote:
To be perfectly honest I don't think it's a good idea to have a bare bottom tank. Fish do like substrates in a tank, it would not be natural for them not to have some kind of substrate. And we all know how much oscars love excavating gravel and sand.
Oscars have been known to choke on gravel. It sure is much easier for me now, with a bare bottom, to keep nitrates under control.
I think gravel substrate is a vestigial remnant of UGFs.
I've thought about trying sand and have read pool filter sand works very well. But I'll just stick with my bare bottom (I painted the underneath a copper color and the oscar quit trying to swim downward).