I think it is virtually impossible to provide any clear conclusions of a DSB
that suddenly "stops working". There are too many variables that would need to be described that could cause a problem or failure to occur in ANY tank setup. Personally, I don't believe as timbo stated that you can identify a DSB
crash as being related to the DSB
itself unless there was an inadequacy created by the hobbyist. I think most of these crashes have been unfairly labeled on the DSB
when there is a much more definitive cause in a lack of bio-diversity, overstocking, overfeeding, etc.
While I give a lot of credibility to Dr. Ron for his invertebrate studies for which he is educated on, I do not follow most of his other speculations that he has created for the hobby as I have seen several without any merit. As I stated before there is absolutely no credible evidence or study proving that a deep sand bed will become a "sink". And there is also no evidence that is can last forever. However, I look towards the success of people like Rob Toonen who have successfully had DSB
's in their tanks as old as 16 years, as well as friends' tanks that are approaching 10 years.
If their is in fact a problem with an end material that has nowhere to go, then indeed EVERY system will eventually fail. This is assuming that some end result indeed gets bound up in the substrate, rock, and animal tissue. If anything, I feel most secure with the longevity of a DSB
over others because there is such a diversity of animals consuming the different forms of matter in the tank. My oldest DSB
is approaching 2 years, still young by some accounts, but I see no evidence of any future problems. Time will tell if this will hold up, but until it happens in my own tank that I know exactly what went on in, I am not going to lend any weight to anyone else's anecdotal evidence stating the contrary.