Alfagrog is the best low cost way to introduce more area into any box type filter or home made filter

This is a 250 word (approx) summary of a chapter from my book. Each chapter or main topic has been summarised in this way. For a complete list of summaries see the right hand column

Concepts:

filter, surface area, Japanese Matting, pond, sand filters, bacteria, turbulence, litre, low cost, Alfagrog, biofiltration, solids, air, vortex, extract.

Summary:

- The single biggest reason for the success of well designed vortex or other filters using Japanese matting with large amounts of air pumped into the vortex biological chambers is to create turbulence which allows excellent mass transfer through maximising concentration differences as required and described above simultaneously with creating large and open surface area structures on which many bacteria can thrive and grow - perfect conditions.

- Although you cannot see it; all solids have been very efficiently removed to prevent clogging of the Japanese matting.

- Only a small proportion of pond keepers can afford or really need large Japanese type matting vortex filters.

- I believe strongly that Alfagrog is the best low cost way to introduce more area into any box type filter or home made filter - throw away those hair curlers, plastic rings, onion bags and whatever else you might use.

- This purpose built ceramic filter medium is very coarse and full of interstices (small holes) allowing massive colonisation on large surface areas for all types of bacteria required in the biofiltration process.

- Because of the high specific surface area (ie surface area per unit volume) which in the case of Alfagrog 40 amounts to a whopping 43 square metres per litre filters can be reduced in size which in turn allows higher levels of turbulence to be achieved or low residence times.

- Sand filters are bad for ponds but great for swimming pools and can only remotely be justified as solid removers.

- The following is an extract from the Aquaculture Dictionary to back up my personal views on sand filters.