Hi Feidhlim, I have your book alternatives to septic tanks, but I have a site with very little fall. I'm not at all technically minded, so would like to avoid pumps. I already have a separator toilet, so I would only be dealing with "greywater" from shower, sinks and washing machine. Could you reccomended a filter that would be good enough to leave the water safe for a greenhouse. I have 20 acres of trees (unfortunately most of them are slightly uphill from the house, those that are down hill are about 40 away. One suggestion is that I gravity feed it to this area and allow it to filter through the trees, but I think I would still need some type of filter first) so I don't want to plant willows as I have no use for the timbre. Thanks for your advice. Regards Abigail P.S. I'm In Co. Roscommon, and have an existing house.