I think that I have thoroughly explained my position on the function and purpose of a gravel bottom aquatic eco-system. Therefore, if one was to construct a lined pond without gravel then a key piece of the total naturally occurring biological cycle is missing; that being the Benthic layer and the accompanying Benthos. Organic detritus would accumulate without sufficient naturally occurring organisms (Benthos) to break it down. A bottom drain would then be appropriate to aid in maintaining overall water quality.
Last edited by tadpole; 04-24-2010 at 06:26 PM.