Wednesday, August 5, 2009
Slow Sand Filter
I prefer the ceramic filter over a slow sand filter, but in an emergency it would be good to know how to make these.
Something to remember is that there is a layer at the top couple of inches in the sand called the hypogeal layer or Schmutzdecke. It contains all the bacteria that help clean the water. Just pouring the water in too fast can wreck it. And it takes a couple of weeks to repair. The same is true with the backflushing. It would be a good idea to have 2 of these, that way if you have to backflush, then the other one is still functioning. Some people use a top diffuser to limit the disturbance when putting water in. And you don't have to use activated carbon. That is mainly for clearing up odors and tastes.