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The filter system is currently working off grid in Upstate NY. I resolved the issue of not being present for weeks at a time and the water getting stagnant with no flow by using a rain barrel timer which releases water once a day to keep waterflow moving throughout the system. I do have a question regarding biochar. Do you recommend acid washing or "treating" the biochar prior to using? or is it fine to just crush it up and use it right after creating it?

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Hello Josh. Thank you for your amazing work.

I have a question about the meshes that are shown on the video. Since the meshes are not in the list of materials, are they necessary or not?

In case they are, do we need to buy something that is alimentary grade?

Thanks

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author

Thanks for your question. The meshes you are referring to are mostly just there for convenience, in case you need to take the layers of media out, it makes the job a little easier. It can also help if you are having more mixing of the size layers than you want. I would say, "not essential, but helpful." If you can get food-grade that would be great! In our case we use things like window screen and poultry netting or shade netting in the field, since those are typically what is available.

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Hello Josh... Can this solution filter salt also?

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Hello All, my 4 barrel set-up is almost complete. If the system needs to be shut down for weeks at a time as it exists in an off- grid camp that is used periodically throughout the year. should all barrels be drained each time? I am also exploring using a timer to drain the clean water tank for a few minutes each day just to keep the flow going? Lastly are there any special instructions for winterizing the system to prevent any unwanted bacteria growth over the winter? Thank you.

Anthony

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The system functions best when water is continually moving through it. Depending upon quality and characteristics of the source water, after a few to several days of inactivity the water could become musty, stale, stagnant. If it is going to be unused for a while it is best to drain the tanks. Then, to restart the system for use, just repeat the startup process of flushing used during initial installation. The biofilm in the sand filter will require some time to fully establish (ripen) as with a new system. For winterizing - just drain the system and pipes to keep them from cracking if the water freezes.

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Hello All. I am trying to figure out if the top of each barrel should be sealed or not. I believe the sand filter barrel needs air to help it do it's thing? Thank you.

Anthony

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author

Hi Anthony, thanks for your question.

You are correct that access to air is beneficial for the biofilm, which does most of the work in the sand filter.

The system as pictured does not need lids on drums to seal the tops. The water level in the system is kept just below the top of the drums by the float valve - so they will not over-flow. This is why it is important for this type of system setup to have all of the drums set on a level surface, so that all of their tops are aligned to the same height. Then the float valve can control the upper water level in all the tanks.

The reason to cover the tops of the drums with screen mesh or lids is to prevent debris from falling into the drums, and to prevent excessive algae growth if the system is exposed to sunlight.

Hope this answers your questions...

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Hi Josh. Thank you for your quick response. My barrels are located on a flat surface but in the woods to keep sunlight to a minimum. Would sealing the barrels with lids be ok and then drill holes in the sand filter lid and screen be sufficient? My major concern is debris and wild life.

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That would be fine, if the lids are vented. If the lids did seal, it could form an air lock, and possible impede system function (i.e., it would pull a vacuum if the water level were to drop). This scenarios is unlikely, but just to be aware. The main objective, as you say, is to keep debris and critters out. Using a lid with vent holes, a screen, or some combination should do the trick.

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Thank you Josh! Much appreciated!!

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Hi josh ,

This is kapil verma from india. I am a advertising photographer by profession. Planning to get into in farming bussiness. Actually i have been searching for good ans chemical free food for my family. I got it from the market but sometime i feel i can't completely trust on other people if they are giving organic food or not. So i decided to start a small farm for my family food requirements.

I am exploring alot about farming without chemical. For chemical free soil and water. As these 2 are most important thing for organic farming. So soil i have got all details. But as we know 70 percent requirement in the farming is water. Soil require less effort to make chemical free but water is a big problem.

Was going through with some of water filter but those are very costly and also these water filter can not purifier water for farming those are good for drinking water.

So xan you suggest mein a good water purifier system technology so that i can purify and chemical free water for my farm in a huge capacity.

Waiting for the reply.

Thanks

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author

Hi Kapil, sorry for the slow reply. I often miss the comments on this site.

There's really no way around a large expense for treating large volumes of water to remove trace chemical contaminants. If there were there wouldn't be so many people studying water treatment technologies! As one of my mentors pointed out to me many years ago, "All the easy problems have already been solved. Only the hard ones are left for us to work out."

Without knowing more about your situation it would be difficult for me to give articular advice. Perhaps you can do an analysis of different water sources available, and select one or more water sources that are relatively protected from contamination? If that is not an option for you, there are various treatment approaches. But what makes the most sense in your situation is very context-dependent. For example, your budget and access to infrastructure and the reliability of that infrastructure.

So there is a lot to think about, and I wonder if there are others in your area working on similar challenges. You could learn from their experiences. Thanks for your interest in this site and let me know if there are specific questions I might could help with.

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Dear Josh, by building your system i discover a big problem: The water will enter the pvc (which contains the string attached to the floater) and go up directly, without going through the gravel filter. So the construction containing the valve has to have a hole to let the string move freely enough, but the hole has to be as tiny as possible. How dis you solve this problem? I hoop that my question is clear enough. (With a drawing it would be more easy to explain). I hope you can help me there. Thank you!

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author

You are correct that some of the water will travel up the pipe used to protect the floater string. However, this is a low proportion of the overall flow.

Also, our alternative arrangements for the gravel filter inlet control (e.g., using other types of float valves positioned at the top of the filter) can obviate this small issue.

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Will it remove arsenic?

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We typically use iron oxygen-/hydroxide based sorbents like granular ferric hydroxide (GFH) or Bayoxide E33 for arsenic removal.

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Thank you so much Sir! I am Chemical Engineer by Profession and working in American water treatment company named as Buckman.That system is bit similar to Gravity filter used for cooling towers.What should be height of first tank from where water will enter in media as it will impact flow.Plz guide.

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