Sour Diesel Grow Journal / Microcontroller Datalogging Experiment - 480w LED RDWC

[jerry]

The Grow
Strain: Sour Diesel from Crop King Seeds
Germination Date: Jan 15, 2018
Nutrients Used: General Hydroponics Grow/Micro/Bloom trio (GMB) and CMPlus Calcium Magnesium supplement
Tent Size: 70cm x 70cm x 160cm
Method: Recirculating DWC using two 5-gallon buckets and hydroton clay
Light: MarsHydro Reflector 96 - Full spectrum 480w

I decided on this reservoir design because I wanted something that would allow me to access the reservoir easily without ever having to move the plant. Since I plan to scrog, I didn't want to risk bumping it against the netting when changing the water. The plant sits in hydroton on top of an air stone in one bucket, with a drip line pumped up from the second bucket. The buckets are connected at the bottom with a piece of electrical conduit. This allows me to easily do reservoir changes without hurting the plant. I also plan on adding a lid to the second bucket eventually. This will be my third hydroponic grow after previously growing master kush and an autoflowering white widow cross. I decided on sour diesel because computer programming with a sativa is awesome. I'm aware that it will stretch more than my indica master kush did, so I plan on using scrog techniques and the overkill strength full spectrum light to compensate for the extra growth.

The Microcontroller
I come from a computer background, and enjoy programming as my other hobby aside from growing weed. I'm pretty lazy, so I wanted to find some way to grow better weed faster with as little effort as possible. As a result, I've been playing around with Arduino microcontrollers to automate my entire grow for me. The microcontrollers are attached to sensors to collect data, and then transmit it over wifi to my computer. Currently, the devices are written in the C++ programming language and logged using Python scripts on my computer. For any developers reading this, the code is all open source and hosted on Github (PM for the link, my github page is associated with some of my professional work and cannabis isn't legal yet where I live). I plan on completing this project in four stages: sensing, analytics, control, and deep learning. Over the duration of the rest of this grow, I plan on focusing on the sensing aspect of the project where I enable sensors to collect all the data to be analyzed. The end goal is to automate the grow process as much as possible, hopefully within the next couple years.

This is currently what the actual device looks like

Right now, it only does temperature and humidity. I plan to also track measures such as Ph, light levels, reservoir temps, etc.​

Germination
The seed was germinated in a peat pellet and placed in the hydroton. The reservoir is filled with clean water and 10ml calmag, Ph'd to 5.8
For the vegetative stage, the lights are on a timer for 18/6 hours of daylight

 

[DoctorJohnson]

Looks great! I'm subscribed.

I have to say, though, that maybe the first place to focus engineering attention is on the mechanics of the grow itself and not the cybernetic component?

A well designed grow with all of the fundamentals in place doesn't really need any more controls than for lights and pumps. Other than that, it's all hand work, doing pruning and LST and mixing the nutes. I guess you could automate pH control (that would be my first choice), but with AN pH Perfect in a big reservoir with good circulation and aeration, even that may not be needed, really.

Thinking about it, I guess one thing that a controller could do that would save a lot of time and energy is the logging. Taking pH measurements and PPM measurements is tedious and time consuming and something that a system could do not just automatically but continuously (and it could even be viewed remotely). That would be very nice.

Here's an interesting link to a super-simple pH meter that would be easy to interface with: http://www.66pacific.com/ph/simplest-ph.aspx

 

[OzBud]

you'll want to cover that second bucket asap to keep the light out of the water.

 

[jerry]

9 Days (Jan 24)

I changed the reservoir today for the first time, and begun the nutrient feeding schedule. Until this point I used just clean Ph'd water with 10ml calmag.

Nutrient solution:

• ~20L clean water
• 7ml micro / 10ml grow / 10ml bloom
• 20ml calmag
• Ph'd to 5.8

 

[jerry]

Yep, I've just been too lazy to go to the hardware store hahaha. I do plan on it - I change the bucket water regularly so its fine for now, but I'll need it to keep leaves and stuff out when the plant gets bigger

 

[jerry]

Thanks! Both the grow and the programming aspects are kind of like separate projects right now. The grow is still a work in progress, and the programming is a long way from being done. By collecting as much data as I can now, I'll have more to work with by the time the programming has become more advanced. The eventual plan is to use Ph, EC, and reservoir temps to calculate the rates that the plant is absorbing nutrients. From there, I can fine tune the nutrient delivery and automate it with servo units, etc.

The actual Ph sensor im using is like the following, I wish I had thought to make one as yours linked is quite interesting! Definitely a consideration for the future, thanks for the post!
https://www.amazon.ca/DFRobot-Analo...UTF8&qid=1517097431&sr=8-1&keywords=ph+sensor

 

[DoctorJohnson]

Nutrient solution:

• ~20L clean water
• 7ml micro / 10ml grow / 10ml bloom
• 20ml calmag

That's a pretty big slug of nutes for a tiny plant. Nebula's recommendation for 20 liters of first feeding is 6.25 ml of micro, grow, and bloom and optionally 25 ml of CaliMagic.

I just made up 20 liters this morning for week 3 recirculating coco coir and used 10 ml of micro, 10 ml of grow, 5 ml of bloom and 20 ml of CaliMagic. (Our water here has no Ca or Mg at all.) My plant is doing great with its diluted version of Nebula's already diluted GH nutes.

Not to mind your business, of course, but seeing as we both mixed the same volume of the same nutes today with quite different concentrations and ratios, I had to comment. I have used Nebula's recommendations before for both DWC and for coco coir, and have found that I can go even lighter than she recommends.

 

[abadtrip]

I am intrested in what u are doing with your sensors I too would love a automated system so I am going to follow along.

u may want to extend your res to outside the tent i personaly hate top feed and feel like it's a waste of time I run half inch feed lines in my RDWC system in to the sides of the pot.

 

[DoctorJohnson]

Ipersonaly hate top feed and feel like it's a waste of time I run half inch feed lines in my RDWC system in to the sides of the pot.

Once the roots hit water, top feed isn't needed, and hydroton will wick water up from the reservoir if you put the bottom layer in the water, so yeah, I personally think you can skip the complexity of top feed if you set things up right. (But people seem to have strong feelings on this sort of thing.)

 

[abadtrip]

I use modifided net pots where there is-a tube up the center of the clay pebbles so my rr sits directly above popping bubbles about 3 inches away from the water line.

 

[gbauto]

I can tell you from experience that you'll get algae growth in both buckets until you make them opaque. Only real harm from algae growth is that it eats your nutes.

 

[gbauto]

It usually takes my new sets about a week of daily hand watering before I get roots in solution I only water once/day during that growth . I originally plumbed my feed line into the base of each netlid but I've found that it's not necessary-I now just let it splash into the bottom of the bucket.

 

[jerry]

That's a pretty big slug of nutes for a tiny plant. Nebula's recommendation for 20 liters of first feeding is 6.25 ml of micro, grow, and bloom and optionally 25 ml of CaliMagic.

I just made up 20 liters this morning for week 3 recirculating coco coir and used 10 ml of micro, 10 ml of grow, 5 ml of bloom and 20 ml of CaliMagic. (Our water here has no Ca or Mg at all.) My plant is doing great with its diluted version of Nebula's already diluted GH nutes.

Not to mind your business, of course, but seeing as we both mixed the same volume of the same nutes today with quite different concentrations and ratios, I had to comment. I have used Nebula's recommendations before for both DWC and for coco coir, and have found that I can go even lighter than she recommends.

Day 13

I think you're right, the plant did look a little hot today. Some research online told me this strain loves lots of nutes, but that may have been a bit much. I changed the reservoir with a new batch of nutes, my cmplus has a little more N than calimagic so I adjusted ratios accordingly and diluted it with an extra ~10L of water

In 30L of water:

• 7.5ml micro
• 12.5ml grow
• 10ml bloom
• 20ml cmplus

I also did some more coding today, I was able to add support to my microcontroller for reading pH values. Turns out my pH sensor electrode is burnt out and I need a new one, but at least it will be plug-and-play when a new one arrives.

 

[DingusKhan]

In fact, I would go even farther and suggest you get black bucket or tote bin and lid for that purpose.

But dood, that is some sick ass shit, yo. I love TGA weed, but I think SubCool should give up his nickname "WeedNerd" to you.
Arduino processors.... giggity!

 

[jerry]

Day 20

After two PH sensors failed at the same time that I ran out of PH testing solution, the PH levels went a bit crazy for a few days. Some of her lower leaves got a bit nitrogen burned, but seems that it recovered well. Lots of new growth the past few days, she looks ready to be topped soon!

I have lots of exciting updates about the sensor programming, but I'll save it all for one post later next week when my sensors arrive in the mail.

Happy growing!

 

[jerry]

Day 22
Topped the plant today after the 6th node started showing the tips of its leaves. I cut down to the 4th node

Day 24
Changed the nutrient solution and modified my reservoir design for better recirculation without a top feed. I was having problems with the ph not balancing correctly between the two buckets, so I rerouted the pump to bring water up to the top of the back bucket. After leaving it on all night, it seemed to stress out the plant and it got all droopy for a bit. I think from now on I'll only turn on the pump for a few minutes to mix up the water after balancing the ph.

In 30L of water:

• 5ml micro
• 7.5ml grow
• 7.5ml bloom
• 10ml cmplus

Day 26
The ph has been rising by about 0.5 every 6 hours since changing the reservoir, it seems to be drinking up all the nutrients really fast! Since adding fresh nutes, it exploded with new growth coming out from the side branches. I also finished making the screen for my scrog. Its been looking a bit droopy, but otherwise healthy!

Day 27
This thing is so dense with growth! I can hardly see the trunk any more. At the base, the trunk is already more than a centimeter wide. It still looks a bit droopy, but still showing lots of new growth so I'm not going to change anything just yet. The ph stopped fluctuating completely today, it's almost like all the nutrients were sucked out of the water in only a few days. Maybe that would explain the sudden burst of new vegetative growth and droopiness? I can't wait to start logging the nutrient solution ppm to get a better idea of whats going on!

The grow space with the screen now in place. It's set up about 7" off the top of the bucket, with 4"x4" grid spaces

Some notes on microcontroller programming
My PH and conductivity sensors came in the mail this week! I've been making some progress on reading data from them bit by bit, it's a busy time of year for me. As of the time of writing this post, I've been able to interface an 8-bit multiplexer for I/O, and I'm currently working on how to read a digital sensor signal across an analog input bus. The ph and conductivity sensors have an analog signal, so they shouldn't be too much trouble (hopefully) once the temp sensors are working.

For the rest of this grow I plan to pretty much only get my controller using the sensors to read in the data, but my long term goal over a few grows is to use the sensor data and control the overall plant environment. With that in mind, I thought it relevant to include some notes on what may work after experimenting and tweaking with my setup.

After messing around with a recirculating design for my reservoir earlier this week, i found that having the pump on 24/7 caused the plant to get droopy really quickly. I'm not sure if this is a result of the extra agitation increasing the speed of nutrient uptake, or the turbulence stressing out the roots, but it seems like it would be worthwhile experimenting with a programmable relay to attach to my controller. This would allow me to control power circuits from my controller, and only have the pump running for a few minutes after a ph balance or adding nutrients to distribute everything evenly across the buckets (in theory).
I also noticed that when my fan was running, the temps and humidity both drop drastically - maybe I could fine-tune the temperature and humidity levels by controlling the fan power as necessary?
And for the ph fluctuations - are the sudden ph swings and droopiness correlated to the nutrient feeding? It almost seems like the plant drank up all the nutes in a couple days with the crazy ph rises, and then stopped abruptly. Maybe this could be balanced a bit better using a controller to slowly dispense nutrients over the course of a week for a more even growth spurt instead of taking them up all at once?
I think it would be pretty cool to automate these things - I'm pretty lazy so the less effort I have to do to grow big healthy plant the better!



Thanks for reading, happy growing!

 

[farmerjim]

Congrats Jerry! Your post has pulled me out from the depths of the "i never post, i just lurk" category! What analytics platforms are you planning on working with? Do you know R at all?

I build frontend analytics/dashboards and am currently learning python and building dashboards in Tableau. I am starting my first grow (DWC) and will be data logging using the Blue Labs Connect Monitor (if all goes as planned) because I don't have the hardware programming background.

Once I get everything up and running I'll share my thread(s), but for now, hello from your new gwe stalker...

 

[jerry]

Hi farmerjim! Welcome, nice to see some other techie people around here. I'm programming my own analytics platform in Python. I've used R a bit, but I'm not as good at it and I already have a bit of preexisting code I can borrow from other work I've done in Python so I'm just gonna do that. As of right now, data is being read from the device broadcasting sensor info over wifi in json format, and then logged via python script to an sqlite database on my local linux server.
For the next few months and the rest of this grow I plan on mostly focusing on the "sensing" aspect to get data to analyze later. I'm programming the device using C++ to record sensor data, which is a learning experience for me as I've never used C++.

If you're a frontend dev working with python, I'd definitely love to chat more over PM! I'm a backend dev / ML and analytics student. I dont have any experience with front end, but maybe you'd like to take a look at what I've got so far in my github repo and see what there is to work with.
I'd happily share my code for my microcontroller if you want to try that route and save a few pennies instead of blue labs, the total hardware cost for my device excluding PH and EC sensors was around $50. The EC and PH sensors were about $100 each. That being said, I've never used blue labs and its likely much more reliable and, well, working already.
I apologize for the lack of updates in regards to the software development part of the grow in the past few weeks, I've been busy with midterms and haven't had much time. Hopefully I'll be able to work on it some more this weekend.

 

[jerry]

Day 32
Topped the six lower branches and pruned the top two

Day 44
I've been doing lots of tucking and bending as it grows! I've been trying to push the fan leaves to the bottom of the plant and spread out the branches to keep it nice and short.
I had a bit of algae growing, so a couple days ago I cleaned out the reservoir and gave it a few coats of paint to help with lightproofing. Still in veg mode so not much else to report yet. Happy growing!

 

[jerry]

Here is a picture of the roots from when I had it out to clean the reservoir