Sorry if this is preexisting.. I'm a bit pressed for time. I am trying to get some activated carbon to make a water filter good enough for showers and washing clothes. My biggest concern here is agricultural run off. I have a very shallow well. my thought is to get some PVC maybe 75 mm ... X 400 mm put a narrow in and out on it... pack it with activated carbon and sand ... I'm curious who may have tried this?? does anyone know what granular size the carbon should be?? can I use regular charcoal temporarily my understanding is that the granular size isn't so much important if I have enough medium for it to go through since it still has to pass over the surface. any ideas would help,, I need to get this done. I have reg charcoal now ... I can get the activated in a few days. oh yea, I have a pump to feed this so my filter should run under pressure from that.
My understanding is that the grain size is crucial for proper filtration. Also, they will deal with bacteria - not with agrichemicals, so it depends on what you are trying to filter out. Charcoal would probably be better for the chemical removal, which you're looking at doing anyway. Hope you get it sorted out effectively.