Terrarium growing experiments

[DirtyCoconuts]

So this has no been almost self sufficient too! Amazing!

[Draikan]

Yeah it's semi-automatic currently.

The RO+fertilizer solution needs to be refilled each weekend. And the tank probably should get checked at about the same time to make sure nothing is too wet or dry. Sometimes the plants need to be moved if they are tending towards soggy or crispy. I have a few flats of other vines and mosses on the rack that need to be watered by hand each weekend too.

While it is low maintenance, it is not providing ideal conditions for the orchids yet. I'm convinced for now that the plants would prefer to be watered more heavily, more frequently, receive more airflow, and have more roots in the air.

[DirtyCoconuts]

Of course they would! But we do what we can with what we have and sometimes that includes time

One think that is really cool about your setup is I bet it is really easy to get in there and work on something. I only have a 10 gallon and a few smaller setups in .5, 1 and a 3 gallon jar/bottle. Everything is hard to reach and I have to use these giant tweezers for everything.

I love how it seems like you can open yours and really get in there

[Draikan]

So I hadn't done any hobby stuff until about May of this year. A friend gifted me an unused 10G aquarium, so I decided to start working on the humidity control and better circulation. I wanted to experiment on an empty tank so i didn't hurt any of my plants.

My goals were to:

1. Use a variable speed fan to provide better, more customizable airflow
2. Accurately measure and log humidity and temperature, to better understand what was happening in the orchid tank
3. Control humidity so the plants can receive more airflow without drying out (basically I wanted to automatically humidify if the tank was getting dry from all the airflow)

At first I was hoping I could buy something to do this, but there just wasn't anything that could quite do what I wanted. Some products come close, but they all lack parts of what I needed.

I looked at a bunch of things, including:
Govee - this is a wireless humidity and temperature monitor, but it is not waterproof, cant control humidity, and cant control a fan.
Neptune Apex - Used to control saltwater aquariums. This is great for controlling an aquarium but they dont have any way to connect fans or humidity sensors.
I also looked at the herpkeeper, from Digital Aquatics, but was dissappointed to see they had gone out of business.

So the only option was to build it myself.

I have been developing and testing an environmental control system for the last few months, using the 10g tank to test it.

This system includes:

1. A wifi module for sending data to the web for logging
2. A speed controlled fan
3. An air temperature and humidity sensor
4. A mister to bump humidity up if it gets too low.

It's all sort of cobbled together on my workbench right now, but it is working great! I will eventually clean it all up into some nice modules so it can be used on other tanks, but for now I am focused on making sure it works as well as possible.

Pictures of tank and controller:




This has been logging controlled environment data from within the tank for just over a month now. You can view live data from the tank here:
IO - Adafruit

I'll post about each of the different parts of this system (fan, mister, sensor), one at a time over the next few days.

---------- Post added at 09:02 PM ---------- Previous post was at 08:58 PM ----------

Impeccable post timing Mr. Coconuts! yeah the size is nice, you can stick your head in and really smell the rainforest!

The big open space in the middle really helps the air movement too. Smaller tanks can be super temperamental. My treefrog tank was a 30G tall (12*18*36 high), and I was always fiddling with it trying to get the air moving evenly without soaking one spot or toasting another.

[Draikan]

I have tested a bunch of fans. Some handle the humidity really well and some die almost instantly.

This one has been running in the orchid tank for over a year with no problems: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

The first fan I used in the test tank died the first time I got it wet. It's really hit or miss when they aren't meant for a wet environment.

When I've used smaller diameter fans in terrariums they've had issues creating even airflow. For the same airflow rate, a smaller fan pushes the same amount of air through a smaller area, so the speed has to be higher. This is louder (annoying) and tends to make "windy" spots in the tank. It's much better to get a big fan, and slow it way down.

So the main things I wanted over typical fans used in terrariums were:
-waterproofing
-a tachometer for measuring speed and checking for stuck or broken fans
-ability to control speed, so I can run the fan at low speed all the time and occasionally bump up to much higher airflow to simulate wind or breeze
-large diameter for gentle airflow and quiet operation

It's not too hard to find computer fans with speed control and a tachometer, you can search "pwm pc fan" on Amazon and a bunch pop up. pwm stands for pulse width modulation, which refers to the signal used to control the speed. It's really hard to find affordable waterproof fans though, there aren't too many choices and they tend to be $50+ ea.

I settled on the Industrial PPC series from Noctua, these are all between $20-$30. They are IP67 rated, which means they are dust proof and can be submerged in water to a depth of 1 meter for up to 30 minutes.

IP ratings for the curious: IP Code - Wikipedia

The noctua fan is working great. It is situated under the mister, and has been constantly wet for weeks. It has a built in tachometer. The speed control works down to 15% of max speed. It's flowrate is 110CFM. This is the exact fan I am using: https://noctua.at/en/nf-a14-industri...-q100-ip67-pwm I may eventually switch to the 160CFM version for even more airflow, but there is a bit of a tradeoff with the 15% minimum speed. At 15% it should be moving about 16CFM, which is still a ton of airflow for a 10g tank, but the automatic mister kicks in to prevent the humidity from getting too low.

This fan is currently running in the test tank, and you can see its speed on the bottom most plots of the dashboard here: IO - Adafruit

Fan in box:
[COLOR="Silver"]

[Leafmite]

Your set up looks great!

[DirtyCoconuts]

Exceptional!

I do not have the skills to do the electronics like that and I am in awe

Have you considered just making a diffuser?
There are a few ways but the easiest is a sheet of plastic with a bunch of holes drilled into it

You could even make one that is mounted on the outside of the tank to blow in dry air (assuming the area around the tank is dryer lol).

I don’t think it is necessary given your nice big fan and the modulation, but it is a good way to make a fan less intense without changing the speed.

Thanks for this thread. Great stuff

[Draikan]

Thanks Leafmite!

I'm an electrical engineer so I've got a bit of a head start on the electronics side. It's the software that slows me down...

Diffuser is a good idea. I'm getting pretty good results just by pointing the fan away from all the plants. there is still a lot of flow in the tank, just not pointing directly at any one plant.

[PlumCrazy]

Wow!!!! Amazing set up! This is almost exactly what I had in mind when I started building mine, but I've got a ways to go. I'm so happy you provided so many specifics - I'll probably use some as I move forward. My hope is also to get to close to full automation. My misting system has shipped, so adding pieces to the puzzle! Thanks for sharing.

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[Draikan]

Glad it's helpful, post pictures of your setup and copy as much as you want!