8 ms·

Automated Hydroponic System Build (2020)

419 points by NegatioN 5y ago

tells 5y ago
I've been mentally planning all of this in my head for when I move to a place with enough space. The amount of detail and research provided in one page is nothing short of astounding. I know I would have never done anything close to this level of work had I done it myself. This level is something else entirely.
madaxe_again 5y ago
This is very impressive. I’m in the midst of implementing an outdoor hydroponics system in much the same vein, except I’m mostly rolling my own sensors using arduino and LoRa for comms, as we are really distributed here - the pi running openhab which runs the show (not just the hydroponics, but energy production and routing, tank levels and pumps, river level monitoring, weather station and generic drip irrigation) is hundreds of meters away from the garden. Finding sensors that weren’t expensive or didn’t require hardwiring was a pita, so just went for very generic modules. Ultrasonics for tank levels and river levels are my favourite so far - something really neat about being able to measure depth without contact, and the modules cost me €6 or something crazy. Commercial gear was all the better part of €1,000 for the same function. It’s all a load of work, but it’s a lot less than managing the homestead by hand. As I’m still in the midst of implementing - I have the physical end largely done, sensors mostly made, logic roughed out - I’m definitely going to be working through his article looking for gotchas. I’ve gotta say, I am curious as to what drove him to build his own platform to run it - openhab works great for home automation stuff, even complicated home automation stuff — and grafana+influxdb give great insights. I digress, but I’m literally trusting it with my life these days, as I’ve built a flood EWS around it - we live on a river that, once in a blue moon, goes crazy - but predictably so - so a simple model around the delta and double delta of level change and precipitation rates (both from our weather station and the one other weather station in the drainage basin with public data, as well as weather forecasts) tells me when it’s time to bug out, and when it’s time to just enjoy the sound of the rain on the roof and the rumble of the river. It proved itself gratifyingly accurate this winter. The river started to look scary, the weather was dreadful, and I was giving only a 5% chance of a flood entering the house - less than 1% of it being a dangerous flood. Evacuated anyway, as I didn’t trust it at that point, but we didn’t flood, and the peak level was within 5cm of forecast. Really short drainage basin makes the river dynamic but very easy to predict. So yeah. Openhab. Super powerful for this kind of thing.
circleit 5y ago
This is obviously nothing less than astounding. I can’t start to describe how incredibly knowledgeable and skilled this person is. Because the topic of hydro and growing food and all that is on HN here, I wanted to leave the following comment on a higher level. Ten years ago I was super dedicated to problems surrounding water, which of course include food and all the issues we have with our food systems. At the pinnacle, I was working with a half acre aquaponics greenhouse in Watsonville, CA. We had 8000 striped bass and produced and incredible amount of fresh produce. It was pesticide free because of you put chemicals on the plants it would get into the water and hurt the fish. It was more “natural” than hydroponics. You weren’t using fertilizer imported from all over, everything in the system could be produced on-site. The more biologically diverse the system was, the more resilient and productive. Both hydro and aqua phonics - the latter of which has been practiced for thousands of years, definitely save a ton of water. But I think aquaponics has a massive chance of being mainstream, especially as automation and all the advanced tech and robots get better. It’s about ecological engineering on a local scale - you are maxing out the ecology to human and nature’s benefit, and there are so many relationships to learn and exploit. It’s strange how impactful this could be on a grand scale - see some Dan barber Ted talks [1] Just really need to get some investment on this on a big scale, like the hydro houses in Canada. No one has, from all that I know, really built aquaponic systems on a grand scale that are economically viable. But I see it coming and after I wrap up my current company, I’m jumping right back in to working on this. We are just going to be doing what nature did best before we murdered all of it…but maybe Mac it out super hard and super quick compared to what it could do. Lastly, with all the climate stuff: Don’t forget, you can’t put a price on the systems that produce the food, water and clean air we breath, cuz you know, we’d be dead. Well maybe we can, but we sure aren’t trying. [1] https://www.ted.com/talks/dan_barber_how_i_fell_in_love_with_a_fish?language=en https://www.ted.com/talks/dan_barber_how_i_fell_in_love_with...
- dmitryminkovsky 5y ago
  I saw a segment 15 years ago about "biodynamic" hydroponics. Not sure if that's a real term or whether I'm even remembering it right, but as I recall the concept was that your grow is more or less a completely closed system that involved fish circulating nutrients through the system. As you say, you don't add nutrients from far off places. The fish feed the plants and the plants feed the fish. In that segment, the fish were tilapia. It seemed perfect and has captured my imagination this whole time.
JoeDaDude 5y ago
Nice work! I tried hydroponics a couple of times, though with a simpler setup. I usually had to combat the build up of algae in the reservoir tank. I was farming outdoors so I blamed sunlight and nutrients for creating conditions for algae growth. I wonder if the use Mycostop would be effective against algae?
- jonathankoren 5y ago
  I suspect it’s sunlight as well. I did hydroponics this year and last year and never had an issue with algae. I kept everything in totes.
- bjelkeman-again 5y ago
  We get algae buildup in our systems if we have exposed water, especially in slow moving water. Any loose algae gets taken away in the Drumfilter.
MegaDeKay 5y ago
I was watching this and wondering if a simplified version of this could be used for mushrooms. Then I saw the very first comment to his YouTube video linking an unlisted video showing a timelapse of oyster mushrooms fruiting. Nice! https://www.youtube.com/watch?v=JVYh4hm-wJ4 https://www.youtube.com/watch?v=JVYh4hm-wJ4
- ozfive 5y ago
  He has a couple projects for mushroom cultivation automation under the projects section of his website. Here is a post where he revisits a previous iteration. https://kylegabriel.com/projects/2015/04/mushroom-cultivation-revisited.html https://kylegabriel.com/projects/2015/04/mushroom-cultivatio...
betwixthewires 5y ago
Having built simple pneumatic and hydraulic systems using relays, sensors and SoCs, this would he an excellent and fun project. It is actually one of my ultimate goals in life to automate a closed system of food production. But one thing, externalizing a lot of the automation to already automated processes i.e. the natural environment is quite useful. You have a general pattern of predictability and the trade off is that it is not granularly predictable but there are less catastrophic failure modes. All in all, if you're on earth it makes the most sense to just grow things outside, or in a passive greenhouse if temperature is a concern. Also to be considered is the more active automation complexity you add, the more narrow the scope will be, so if you're tightly controlling nutrients for example, you're restricted on what variety you can have. If you consider the plants active participants in the system as opposed to subjects to or of the system you can devise a much easier system to construct, a la permaculture.
- ampdepolymerase 5y ago
  What you want is a growth chamber.
- tharkun__ 5y ago
  Same dream here. I just never have time or space ;) I make due with with the garden in the meantime. As you say a lot of it is just free in nature. Nutrients are in the compost (I have a lot of trees meaning leaves that I compost with grass clippings, kitchen scraps and guinea pig poop) and sun and water are free and automatic most of the times. The problem comes in when these don't cooperate. A few years ago my corn was unusable. Too wet and I'm not sure what exactly it was but it had this black fungus-y stuff. Threw it all out. Then it was too dry so I had to add an automated watering system as the rain barrels couldn't keep up. This year I haven't had to use it yet. I can't even really use the overflowing rainbarrels because it keeps raining once a week (mainly have potatoes this year). What I really like is fruit trees. Very very hands off after getting them established. Unfortunately they are mainly for fresh eating and jam, so not really food production in that sense. But sure as hell very tasty all year round! I can recommend sour cherries. The sour of the cherries is awesome once made into jam and personally I will eat them right off the tree too. Not many worms either.
s0rce 5y ago
Have you thought about using weak acid cation ion exchange resins to control pH?
- deathemperor 5y ago
  interesting. could you point to more details? I'd like to know more since I'm a fish breeder and a lot of fishes need a controlled environment for breeding.
  - s0rce 5y ago
    There are a variety of papers on the topic for hydroponics (see below) using weak acid cation resins with reciculation to control pH so you don't need to constantly replace buffers or use pH up/down chemical additions either, there are also some forum threads and reddit posts, some related to marijuana hydroponics. I suspect the same approach could work for fish breeding depending on marine/fresh water. https://www.researchgate.net/publication/11808440_Stabilization_of_pH_in_Solid-matrix_Hydroponic_Systems https://www.researchgate.net/publication/11808440_Stabilizat... https://www.tandfonline.com/doi/abs/10.1080/01904169209364369 https://www.tandfonline.com/doi/abs/10.1080/0190416920936436... https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1399-3054.1976.tb04852.x https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1399-3054....
    - deathemperor 5y ago
      thanks for the sources. I'll be digging deeper.
mastazi 5y ago
I have been in the aquarium hobby in the past, so when I started looking into hydroponics, for me the natural outcome was to also look into aquaponics[1]. What I like the most about aquaponics (and recirculating hydroponics) is the sustainability aspects, it is an almost completely closed-loop system, with relatively small external inputs compared to other farming methods, and extremely small water requirements (due to the fact that water is continuously recycled). Two bits of info about aquaponics that not many people know: 1. it is possible to have aquaponics systems in a vegetarian context: in many cases the fish is not for human consumption as food (in large commercial systems this is usually koi that is sold as ornamental fish[2a], in smaller systems goldfish kept as pets[2b]). 2. there are aquaponics systems that don't require access to electricity, in particular the iAVS system (a.k.a "sandponics") was developed with subsistence farmers that had no electricity access in mind, it doesn't require water to be pumped continuously, rather you are only required to manually recirculate the water a few times a day which can be achieved with a bucket or other low tech solutions[3]. [1] https://en.wikipedia.org/wiki/Aquaponics https://en.wikipedia.org/wiki/Aquaponics [2a] https://www.pvrkoicentre.com/pages/aquaponics https://www.pvrkoicentre.com/pages/aquaponics [2b] https://farmingaquaponics.com/caring-for-goldfish-in-aquaponics-systems/ https://farmingaquaponics.com/caring-for-goldfish-in-aquapon... [3] https://garydonaldson.net/home/iavs/ https://garydonaldson.net/home/iavs/
- lemmox 5y ago
  I set-up an aquaponic system on my front porch a few years ago. My wife was skeptical but I grew some of the finest basil around. Just used a tote filled with goldfish, some PVC piping, and a pump. Unfortunately one evening the raccoons figured out how to pop the lid off the tote - it was a massacre!
  - mastazi 5y ago
    Oh no! I had goldfish as pets I can imagine that must have been sad. At least they died for "natural" causes.
    - lemmox 5y ago
jbuhbjlnjbn 5y ago
As a side note, the way the plants and electronics are interwoven is summoning strange emotions for me, an Akira'esqe picture... There are two main ways these days to do natural farming, one is back to the roots, the other one is this high-tech, putting all advancements we got into it. Straight out of a sci-fi movie if you ask me.
theCodeStig 5y ago
Unfortunately these DIY systems are usually made with PVC. I think it’s worthwhile, to purchase a ready made system that uses food grade plastic, as I have done.
- papercrane 5y ago
  PVC is a food safe plastic. There are some PVC products treated with things that make them not food safe, but as long as it has a NSF-51 marking it's food grade.
  - AbrahamParangi 5y ago
    I’d expect the concern is about plasticizers leaching from the PVC. They’re not “toxic” but they are possibly endocrine disruptors.
libertine 5y ago
This is great, and this also means that it's possible to artificially create an environment of scarcity to the plants, which apparently is great for our longevity, like David Sinclair pointed out [1]. [1] https://www.youtube.com/watch?v=mmRzeD4_41M&t=314s https://www.youtube.com/watch?v=mmRzeD4_41M&t=314s
sefoc 5y ago
Really cool idea, I was looking into this for creating a business
nkingsy 5y ago
Hydro doesn’t taste as good as organic, and it needs to be flushed or you ingest a lot of nitrates, which is likely carcinogenic. Flushing requires careful planning and a system designed for it. You can’t just treat it like a fridge full of food. With soil you can just leave stuff in the ground until you want to eat it. I’ve poured a lot of time and money into the hobby, and have settled on organic soil with some simple drip for indoor growing. The water use is about the same. As long as you’re indoor the water has nowhere to runoff/evaporate to. IMO the benefits of hydro/Aquaponics are nonexistent. Also, the whole system is a pile of plastics. The tote and drain pipe in the linked article are not food grade plastic, which would scare me away from this system. The automation is way way way overkill. Hydro is very easy to tweak. The nutrient profile is a tiny percentage of the labor, and a $3 battery operated temp/humidity display is plenty for keeping things nice for the plants. They show the high and low since last reset, which is all you need. If I had any outdoor space with good sun I would set up a greenhouse, but since I don’t have that I run leds directly off of solar panels on my roof (dc-dc step ups and downs as needed). Kind of cool to see them rise and set with the sun.
- millzlane 5y ago
  Honestly, there is research out there that is a couple of years old that disproves the need for flushing. This is the first link I found. And the first of it's study that I know of. https://www.rxgreentechnologies.com/wp-content/uploads/2019/11/FlushingTimes_TrialReport.pdf https://www.rxgreentechnologies.com/wp-content/uploads/2019/... I'll see if I can locate the talk from Dr. Bruce Bugbee on flushing.
  - nkingsy 5y ago
    I’ve found that herbs like cilantro taste extra strong when unflushed (even I taste the soapy thing, which I don’t normally) I take my cues from the cannabis hobbyists, and they’ve largely moved away from hydro because of the taste. Unflushed bud is known to be harsh, give a nasty headache, and leave extra salts in the ash for those who smoke it.
    - 5y ago
jmheflin 5y ago
Awesome build and write up. I used to work for a company called AEssense making automated aeroponic systems for commercial cannabis growers. They are still around and have installs all over the US. Many similar features to your NFT system. Cool stuff!
vladTheInhaler 5y ago
I was interested in a build like this a few years back, but I was put off by the price of the sensors. Seems like not much has changed, unfortunately.
71a54xd 5y ago
Reminds me of this automated aquarium controller build from a now defunct personal blog! https://web.archive.org/web/20140313035949/http://kill-9.me/tag/aquarium https://web.archive.org/web/20140313035949/http://kill-9.me/...

419 points by NegatioN 5y ago

I've been mentally planning all of this in my head for when I move to a place with enough space. The amount of detail and research provided in one page is nothing short of astounding. I know I would have never done anything close to this level of work had I done it myself. This level is something else entirely.

madaxe_again 5y ago

This is very impressive. I’m in the midst of implementing an outdoor hydroponics system in much the same vein, except I’m mostly rolling my own sensors using arduino and LoRa for comms, as we are really distributed here - the pi running openhab which runs the show (not just the hydroponics, but energy production and routing, tank levels and pumps, river level monitoring, weather station and generic drip irrigation) is hundreds of meters away from the garden. Finding sensors that weren’t expensive or didn’t require hardwiring was a pita, so just went for very generic modules. Ultrasonics for tank levels and river levels are my favourite so far - something really neat about being able to measure depth without contact, and the modules cost me €6 or something crazy. Commercial gear was all the better part of €1,000 for the same function. It’s all a load of work, but it’s a lot less than managing the homestead by hand. As I’m still in the midst of implementing - I have the physical end largely done, sensors mostly made, logic roughed out - I’m definitely going to be working through his article looking for gotchas. I’ve gotta say, I am curious as to what drove him to build his own platform to run it - openhab works great for home automation stuff, even complicated home automation stuff — and grafana+influxdb give great insights. I digress, but I’m literally trusting it with my life these days, as I’ve built a flood EWS around it - we live on a river that, once in a blue moon, goes crazy - but predictably so - so a simple model around the delta and double delta of level change and precipitation rates (both from our weather station and the one other weather station in the drainage basin with public data, as well as weather forecasts) tells me when it’s time to bug out, and when it’s time to just enjoy the sound of the rain on the roof and the rumble of the river. It proved itself gratifyingly accurate this winter. The river started to look scary, the weather was dreadful, and I was giving only a 5% chance of a flood entering the house - less than 1% of it being a dangerous flood. Evacuated anyway, as I didn’t trust it at that point, but we didn’t flood, and the peak level was within 5cm of forecast. Really short drainage basin makes the river dynamic but very easy to predict. So yeah. Openhab. Super powerful for this kind of thing.

circleit 5y ago

This is obviously nothing less than astounding. I can’t start to describe how incredibly knowledgeable and skilled this person is. Because the topic of hydro and growing food and all that is on HN here, I wanted to leave the following comment on a higher level. Ten years ago I was super dedicated to problems surrounding water, which of course include food and all the issues we have with our food systems. At the pinnacle, I was working with a half acre aquaponics greenhouse in Watsonville, CA. We had 8000 striped bass and produced and incredible amount of fresh produce. It was pesticide free because of you put chemicals on the plants it would get into the water and hurt the fish. It was more “natural” than hydroponics. You weren’t using fertilizer imported from all over, everything in the system could be produced on-site. The more biologically diverse the system was, the more resilient and productive. Both hydro and aqua phonics - the latter of which has been practiced for thousands of years, definitely save a ton of water. But I think aquaponics has a massive chance of being mainstream, especially as automation and all the advanced tech and robots get better. It’s about ecological engineering on a local scale - you are maxing out the ecology to human and nature’s benefit, and there are so many relationships to learn and exploit. It’s strange how impactful this could be on a grand scale - see some Dan barber Ted talks [1] Just really need to get some investment on this on a big scale, like the hydro houses in Canada. No one has, from all that I know, really built aquaponic systems on a grand scale that are economically viable. But I see it coming and after I wrap up my current company, I’m jumping right back in to working on this. We are just going to be doing what nature did best before we murdered all of it…but maybe Mac it out super hard and super quick compared to what it could do. Lastly, with all the climate stuff: Don’t forget, you can’t put a price on the systems that produce the food, water and clean air we breath, cuz you know, we’d be dead. Well maybe we can, but we sure aren’t trying. [1] https://www.ted.com/talks/dan_barber_how_i_fell_in_love_with_a_fish?language=en https://www.ted.com/talks/dan_barber_how_i_fell_in_love_with...

dmitryminkovsky 5y ago
I saw a segment 15 years ago about "biodynamic" hydroponics. Not sure if that's a real term or whether I'm even remembering it right, but as I recall the concept was that your grow is more or less a completely closed system that involved fish circulating nutrients through the system. As you say, you don't add nutrients from far off places. The fish feed the plants and the plants feed the fish. In that segment, the fish were tilapia. It seemed perfect and has captured my imagination this whole time.

JoeDaDude 5y ago

Nice work! I tried hydroponics a couple of times, though with a simpler setup. I usually had to combat the build up of algae in the reservoir tank. I was farming outdoors so I blamed sunlight and nutrients for creating conditions for algae growth. I wonder if the use Mycostop would be effective against algae?

jonathankoren 5y ago
I suspect it’s sunlight as well. I did hydroponics this year and last year and never had an issue with algae. I kept everything in totes.
bjelkeman-again 5y ago
We get algae buildup in our systems if we have exposed water, especially in slow moving water. Any loose algae gets taken away in the Drumfilter.

MegaDeKay 5y ago

I was watching this and wondering if a simplified version of this could be used for mushrooms. Then I saw the very first comment to his YouTube video linking an unlisted video showing a timelapse of oyster mushrooms fruiting. Nice! https://www.youtube.com/watch?v=JVYh4hm-wJ4 https://www.youtube.com/watch?v=JVYh4hm-wJ4

ozfive 5y ago
He has a couple projects for mushroom cultivation automation under the projects section of his website. Here is a post where he revisits a previous iteration. https://kylegabriel.com/projects/2015/04/mushroom-cultivation-revisited.html https://kylegabriel.com/projects/2015/04/mushroom-cultivatio...

betwixthewires 5y ago

Having built simple pneumatic and hydraulic systems using relays, sensors and SoCs, this would he an excellent and fun project. It is actually one of my ultimate goals in life to automate a closed system of food production. But one thing, externalizing a lot of the automation to already automated processes i.e. the natural environment is quite useful. You have a general pattern of predictability and the trade off is that it is not granularly predictable but there are less catastrophic failure modes. All in all, if you're on earth it makes the most sense to just grow things outside, or in a passive greenhouse if temperature is a concern. Also to be considered is the more active automation complexity you add, the more narrow the scope will be, so if you're tightly controlling nutrients for example, you're restricted on what variety you can have. If you consider the plants active participants in the system as opposed to subjects to or of the system you can devise a much easier system to construct, a la permaculture.

ampdepolymerase 5y ago
What you want is a growth chamber.
tharkun__ 5y ago
Same dream here. I just never have time or space ;) I make due with with the garden in the meantime. As you say a lot of it is just free in nature. Nutrients are in the compost (I have a lot of trees meaning leaves that I compost with grass clippings, kitchen scraps and guinea pig poop) and sun and water are free and automatic most of the times. The problem comes in when these don't cooperate. A few years ago my corn was unusable. Too wet and I'm not sure what exactly it was but it had this black fungus-y stuff. Threw it all out. Then it was too dry so I had to add an automated watering system as the rain barrels couldn't keep up. This year I haven't had to use it yet. I can't even really use the overflowing rainbarrels because it keeps raining once a week (mainly have potatoes this year). What I really like is fruit trees. Very very hands off after getting them established. Unfortunately they are mainly for fresh eating and jam, so not really food production in that sense. But sure as hell very tasty all year round! I can recommend sour cherries. The sour of the cherries is awesome once made into jam and personally I will eat them right off the tree too. Not many worms either.

s0rce 5y ago

Have you thought about using weak acid cation ion exchange resins to control pH?

deathemperor 5y ago
interesting. could you point to more details? I'd like to know more since I'm a fish breeder and a lot of fishes need a controlled environment for breeding.
- s0rce 5y ago
  There are a variety of papers on the topic for hydroponics (see below) using weak acid cation resins with reciculation to control pH so you don't need to constantly replace buffers or use pH up/down chemical additions either, there are also some forum threads and reddit posts, some related to marijuana hydroponics. I suspect the same approach could work for fish breeding depending on marine/fresh water. https://www.researchgate.net/publication/11808440_Stabilization_of_pH_in_Solid-matrix_Hydroponic_Systems https://www.researchgate.net/publication/11808440_Stabilizat... https://www.tandfonline.com/doi/abs/10.1080/01904169209364369 https://www.tandfonline.com/doi/abs/10.1080/0190416920936436... https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1399-3054.1976.tb04852.x https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1399-3054....
  - deathemperor 5y ago
    thanks for the sources. I'll be digging deeper.

mastazi 5y ago

I have been in the aquarium hobby in the past, so when I started looking into hydroponics, for me the natural outcome was to also look into aquaponics[1]. What I like the most about aquaponics (and recirculating hydroponics) is the sustainability aspects, it is an almost completely closed-loop system, with relatively small external inputs compared to other farming methods, and extremely small water requirements (due to the fact that water is continuously recycled). Two bits of info about aquaponics that not many people know: 1. it is possible to have aquaponics systems in a vegetarian context: in many cases the fish is not for human consumption as food (in large commercial systems this is usually koi that is sold as ornamental fish[2a], in smaller systems goldfish kept as pets[2b]). 2. there are aquaponics systems that don't require access to electricity, in particular the iAVS system (a.k.a "sandponics") was developed with subsistence farmers that had no electricity access in mind, it doesn't require water to be pumped continuously, rather you are only required to manually recirculate the water a few times a day which can be achieved with a bucket or other low tech solutions[3]. [1] https://en.wikipedia.org/wiki/Aquaponics https://en.wikipedia.org/wiki/Aquaponics [2a] https://www.pvrkoicentre.com/pages/aquaponics https://www.pvrkoicentre.com/pages/aquaponics [2b] https://farmingaquaponics.com/caring-for-goldfish-in-aquaponics-systems/ https://farmingaquaponics.com/caring-for-goldfish-in-aquapon... [3] https://garydonaldson.net/home/iavs/ https://garydonaldson.net/home/iavs/

lemmox 5y ago
I set-up an aquaponic system on my front porch a few years ago. My wife was skeptical but I grew some of the finest basil around. Just used a tote filled with goldfish, some PVC piping, and a pump. Unfortunately one evening the raccoons figured out how to pop the lid off the tote - it was a massacre!
- mastazi 5y ago
  Oh no! I had goldfish as pets I can imagine that must have been sad. At least they died for "natural" causes.
  - lemmox 5y ago

jbuhbjlnjbn 5y ago

As a side note, the way the plants and electronics are interwoven is summoning strange emotions for me, an Akira'esqe picture... There are two main ways these days to do natural farming, one is back to the roots, the other one is this high-tech, putting all advancements we got into it. Straight out of a sci-fi movie if you ask me.

theCodeStig 5y ago

Unfortunately these DIY systems are usually made with PVC. I think it’s worthwhile, to purchase a ready made system that uses food grade plastic, as I have done.

papercrane 5y ago
PVC is a food safe plastic. There are some PVC products treated with things that make them not food safe, but as long as it has a NSF-51 marking it's food grade.
- AbrahamParangi 5y ago
  I’d expect the concern is about plasticizers leaching from the PVC. They’re not “toxic” but they are possibly endocrine disruptors.

libertine 5y ago

This is great, and this also means that it's possible to artificially create an environment of scarcity to the plants, which apparently is great for our longevity, like David Sinclair pointed out [1]. [1] https://www.youtube.com/watch?v=mmRzeD4_41M&t=314s https://www.youtube.com/watch?v=mmRzeD4_41M&t=314s

sefoc 5y ago

Really cool idea, I was looking into this for creating a business

nkingsy 5y ago

Hydro doesn’t taste as good as organic, and it needs to be flushed or you ingest a lot of nitrates, which is likely carcinogenic. Flushing requires careful planning and a system designed for it. You can’t just treat it like a fridge full of food. With soil you can just leave stuff in the ground until you want to eat it. I’ve poured a lot of time and money into the hobby, and have settled on organic soil with some simple drip for indoor growing. The water use is about the same. As long as you’re indoor the water has nowhere to runoff/evaporate to. IMO the benefits of hydro/Aquaponics are nonexistent. Also, the whole system is a pile of plastics. The tote and drain pipe in the linked article are not food grade plastic, which would scare me away from this system. The automation is way way way overkill. Hydro is very easy to tweak. The nutrient profile is a tiny percentage of the labor, and a $3 battery operated temp/humidity display is plenty for keeping things nice for the plants. They show the high and low since last reset, which is all you need. If I had any outdoor space with good sun I would set up a greenhouse, but since I don’t have that I run leds directly off of solar panels on my roof (dc-dc step ups and downs as needed). Kind of cool to see them rise and set with the sun.

millzlane 5y ago
Honestly, there is research out there that is a couple of years old that disproves the need for flushing. This is the first link I found. And the first of it's study that I know of. https://www.rxgreentechnologies.com/wp-content/uploads/2019/11/FlushingTimes_TrialReport.pdf https://www.rxgreentechnologies.com/wp-content/uploads/2019/... I'll see if I can locate the talk from Dr. Bruce Bugbee on flushing.
- nkingsy 5y ago
  I’ve found that herbs like cilantro taste extra strong when unflushed (even I taste the soapy thing, which I don’t normally) I take my cues from the cannabis hobbyists, and they’ve largely moved away from hydro because of the taste. Unflushed bud is known to be harsh, give a nasty headache, and leave extra salts in the ash for those who smoke it.
  - 5y ago

jmheflin 5y ago

Awesome build and write up. I used to work for a company called AEssense making automated aeroponic systems for commercial cannabis growers. They are still around and have installs all over the US. Many similar features to your NFT system. Cool stuff!

vladTheInhaler 5y ago

I was interested in a build like this a few years back, but I was put off by the price of the sensors. Seems like not much has changed, unfortunately.

71a54xd 5y ago

Reminds me of this automated aquarium controller build from a now defunct personal blog! https://web.archive.org/web/20140313035949/http://kill-9.me/tag/aquarium https://web.archive.org/web/20140313035949/http://kill-9.me/...