rshimek
11/22/1999, 01:53 PM
Gerry's point is well taken, but...
The small stars and amphipods are not the major actors in your sand bed fauna. Those animals are the small polychaete annelids, nematodes, flatworms, and other interstitial and sand animals, as well as foraminiferans, other protozoans and bacteria.
Generally with a decent mix of grain sizes in sand, the larger particles will soon migrate to the surface. They do this in response to sediment disturbances such as burrowing. The larger fauna such as the amphipods, small ophiuroids (brittle/serpent stars), etc., will occupy this level of sediment and move food and detritus through and into it. The other sand fauna will occupy the finer sediments beneath it and will continue the processing. Bacterial processing (i. e. the biological filter) is maximized in the fine sand under low oxygen or anaerobic conditions.
Coarser material provides only for one component of multicomponent systems.
Most commercial systems use coarser material as it resists the continual disturbance factors introduced in these systems by harvesting, etc. It really isn't the best stuff for you to use in your systems.
Cheers, Ron
The small stars and amphipods are not the major actors in your sand bed fauna. Those animals are the small polychaete annelids, nematodes, flatworms, and other interstitial and sand animals, as well as foraminiferans, other protozoans and bacteria.
Generally with a decent mix of grain sizes in sand, the larger particles will soon migrate to the surface. They do this in response to sediment disturbances such as burrowing. The larger fauna such as the amphipods, small ophiuroids (brittle/serpent stars), etc., will occupy this level of sediment and move food and detritus through and into it. The other sand fauna will occupy the finer sediments beneath it and will continue the processing. Bacterial processing (i. e. the biological filter) is maximized in the fine sand under low oxygen or anaerobic conditions.
Coarser material provides only for one component of multicomponent systems.
Most commercial systems use coarser material as it resists the continual disturbance factors introduced in these systems by harvesting, etc. It really isn't the best stuff for you to use in your systems.
Cheers, Ron