Water purification filter

Ok, as most of you know Im the resident cheap skate, so heres the question, what would be the cheapest effective water filtering system that you dont have to replace the filters in all the time? Better yet dose anyone know how to build one yourself? From what Ive heard the Berkeys would be great but I understand they also run like $200+ most of the time. I would like to come up with a means of makeing potable water that dosnt have to have replacement filters but also as cheap as I can get and DIY would be ideal. Any sugestions?

 

A pant leg with the bottom tied, a couple of handfuls of charcoal dumped in, and the rest of the leg filled with sand. Still gotta boil it, but it will filter out most of the organisms and mud.

 

It wouldnt have to be convenient to lug around all the time so a 5 gallon bucket would likely work. I may be off on it but I understand that the berkeys use a ceramic filter? Would water filter through a flower pot if you got one with out the hole in the bottom in a similar way or am I way off here?

 

When money permits I figure I probably will get a Berkey, basicly trying to come up with something in case one is needed in the meantime. I realy dont have a whole lot to sell off and as far as guns, definatly not enouph to be selling any off and also no one of my guns would bring enouph so theat would mean 2 or 3 of them, aproaching 1/2 of all the guns in the house. Hopefuly I can get set up and rolling on makeing knives soon and that may help out a lot if I can get them done well enouph to bring a decent price, then I can buy more of the stuff I need or would like to have.

 

Precipitation
Numerous methods for precipitating the salt out of sea water to make it potable have been tested at the Naval Medical Research Institute; the process finally adopted bothby the Navy Bureau of Aeronautics and by the Air Force is the one developed by thePermutit Company for demineralizing sea water. The essential materials for the Permutit method aresilver zeolite and a plastic bag
in which to carry on the reactions of demineralizing the salt water. These minerals are made up into a small kit contained in a metal box. The silver zeolite is compressed into a briquette, six of which are packedin the kit. The plastic bag holds a pint of water and is fitted at one end with a cotton disc filter and a tube through which water may be withdrawn; the other end is open, but is rolled up and fastened after filling the bag.

To use, the bag is filled with sea water to the pint mark, one briquette of silver zeolite is added, and then the bag is kneaded for 20 minutes to break up the briquette and to allow the reaction of the silv
er zeolite with the sodium chloride. Silver chloride and sodium zeolite are products of this reaction,
both of which precipitate according to the following equation:
2NaCl(aq) + Ag 2 Z(s) = = > 2AgCl(s) + Na2Z(s)
About 80% of the total solids in the sea water are removed by this reaction making the water suitable to drink without being distasteful and without producing undue thirst. The treated water can be removed to another vessel or taken directly from the outlet tube of the plastic bag. The precipitated solids arewashed out with salt water and the bag is ready for use again. Only 6 briquettes are furnished with each kit because the cotton disc filter becomes too clogged for further use after this number of filtrations. No economically feasible ion exchange process has yet been developed which will demineralize sea water in larger quantities.


http://www.bluewaternavy.org/distillation/Water treatment.pdf
anyone familiar with this method of desal?

 

Solar distillation works, but is not as fast. and I believe it takes a few times to accomplish full distillation.