6. On top of your finer sand, add a 1-2” layer of coarser sand. Think paver sand. This stuff can range a bit from tiny pebbles to decomposed granite or limestone, as long as the grains are larger than the fine sand below.
7. Your next layer should consist of small pebbles and very coarse sand. If you’re near a river, dry creek, or drainage area, this can often be found along the banks or in the river bed itself.
8. The top layer consists of actual gravel, 1-2” of the stuff. Typically, I aim for a completely full bottle, so if there are 2-3” left, I just fill them with gravel.
9. Last, take the other half of your bandana, or a nice big piece of cloth and place it over the hole that you cut in Step 2. Use a rubber band or a piece of paracord to tie the cloth over the opening. Now you’re ready to filter some water.
Great article fellas. One little tip from an 80 year old survivalist. Make sure that after every few filters that you pour a cup of boiling water through the filter system. it takes of any little survivors that might be lingering around thinking they escaped the process. Keep up the good tips.
Rip