So i have a large pond on a farm. If anything happens id like to be able to go down, get some water and purify for use in home.
Have well water now, the spring feeds the pond. I mention the farm thing bc of fertilizers and other potential runoff. We dont drink our home water rn but use it for brushing teeth and ice cubes. Its been tested and isnt bad but has some turbidity so its not aesthetically appealing.
One of the best filter system on the market are the Berkey filters. They are also expensive and they charge a lot for replacement filters.
That said... if you go on Amazon and look up the filter elements for the Big Berkey filter system, you will find knock-off versions of their filter cartridges that are also highly rated for 1/3rd the price also on Amazon. Berkey charges about $180 for 2 filters. You can get similar knock-off versions for about $60 for 2 filters.
You can buy these activated charcoal filter elements, then easily build your own system using either stainless steel pots or using 5 gallon food grade plastic buckets. If I wanted a gravity flow system where I could pour water through a strainer on one end and have the water crystal clear and drinking quality as an outflow... that's my preference.
They are great: I've had mine a while now and am amazed at how much my skin has changed.