Last night I asked a simple question, and Brad gave me a simple answer, which I appreciated. Now when I wanted to give a bit of a rebuttal (not an argument), the thread has really grown. But I still want to make a small point if allowed. The point was that given the small grain size of a typical sandbed, and each grain can be colonised by bacteria. You would need tons, and tons of rock to equal the area for bacteria to colonise. I hope that makes sense, as I am having a problem with the sentence structure.
In addition some time ago when I hung around Aquaria Central there was a thread about sandbeds where a guy really was upset, and told us the inherent danger of sandbeds crashing, and killing everything. The outcome of that discussion was that there was almost no anecdotal evidence of such a thing happening.
I myself have smaller tanks (the largest being a 50), and consequently I have moved sandbeds a number of times. The only time I noticed some H2S was when I had a six inch sandbed. Since that time I keep sandbeds down to four inches without any problems.
I hope I did not bore you with this.
