Re: Substrate Preparation

When I was running experiments on rooted aquatic plants I used a 
substrate from a local lake. In an attempt to control what organisms came 
out of the sediment I autoclaved them before use ... I was amazingly 
unpopular as I could stink up a seven story building with ease! In 
retrospect, this was mostly unnecessary and not particularly effective 
... many aquatic organisms have dormant phases which are extremely 
resistant to damage. 
One of the emerging areas of interest in aquatic 
botany and toxicology is the effect of sediment composition on plant 
growth. As you can imagine this is a difficult area of study due to the 
complex and heterogenous nature of saturated sediments ... with this in 
mind it is difficult to know whether one should worry about sediment 
pathogens or not but I dont and have never had a noticeable problem.

Dr. dave.