Long term water purification

[Luci_ferson]

its not to difficult to build your own portable sand and charcoal filter.
(its only experimental at the moment but appears to be working)

All you need is a piece of pipe (like the waste pipe of your washing machine ) about 3 foot in length. (probably could be smaller)
put a cap on the bottom with a few holes in and then put a small layer of sharp clean gravel.
above that put finer grained gravel
then a cotton wool filter layer and above it some more fine gravel. then a layer of sand then the top layer is activated charcoal.
with a final filter of more cotton wool before placing on another cap with holes in
this is the top where the water comes out
pump water in the bottom slowly until it comes out of the top .
collect the clean water from the top.

so far ive tested the water using my aquariums test kit.
the water I used was a mix of puddle water and urine (I didn't drink it afterwards)

it tests negative for nitrates, nitrites, and ammonium
but its Carbonate hardness increases as does its ph. (which was expected)

the original prototype fed the other way round top to bottom but although it worked the water had a slight cloudiness to it.
feeding from bottom and taking from the top seems to allow gravity to keep more of the particulate matter to be retained in lower levels.

At the moment I still intend to boil it afterwards for drinking.and obviously id try not to take water from sources that were likely to contain urine (that was only experimental).