WIP: Fridge terrarium for cool growers

[theorchidapartment]

As a NYC apartment dweller, I've been limited to intermediate/warm species that can tolerate the heat on summer days when the window unit AC can't keep up and cold winter days when the radiators are going gangbusters.

But there are so many cool growers out there I want to grow! After reading about various cooling methods, I decided the most reliable setup for my environment would be a refrigerator hooked up to a programmable temperature controller.

I searched eBay and Craigslist for months until this beauty came along:



It's a Hoshizaki display case that I bought from a couple who closed their chocolate store... so it's got a sweet history! *rimshot* It has a built-in florescent bulb & glass sliding doors (not pictured).

First order of business was to separate the circuit for the florescent light and the refrigerator so I could run them independently; the former on a timer and the latter on a temperature controller. I was able to follow the wiring diagram and separate out the ends of the lighting circuit (the black and white cords with masking tape; electrical tape around the clusters they came from):



I cut off the socket end of an old extension cord and stripped the wires:



Then I attached the light to the plug and capped everything:



Let there be light!



Mission accomplished: the original grounded plug powers the refrigerator and the non-grounded plug powers the light:



I had to rearrange my shelves a number of times before finally arriving at this setup (I need a taller shelving unit!):



Next step is to need to get the controller and fans as well as a brighter daylight bulb. I'm thinking of getting the Inkbird ITC-310T, which will let me set separate daytime and nighttime temps, but I am open to suggestions!

Will continue to update this thread as I turn this display fridge into a cool-growing terrarium! I'm already thinking about what I could grow in here and would love to hear about everyone's favorite cool growers!

[Draikan]

A refrigerated tank is quite a challenge but you are off to a great start!

Are you able to insulate any surfaces that won't be used for viewing? Even something as simple as sticking styrofoam to the back wall on the outside could significantly reduce the cooling load on the compressor.

Does this thing have a drain? May want to keep an eye out for condensation putting water where there shouldn't be any. This includes outside the tank, if you get condensation on the outer surface (not sure what your indoor climate is like humidity wise).

Also may want to consider a small circulation fan inside to help distribute the cool air and keep the climate from getting too extreme anywhere.

I also wonder if the compressor could be speed controlled... does it have a nameplate?

[Subrosa]

Simply replacing the fluorescent tube isn't going to give you that much more light, as you're limited to using the same wattage tube. You're probably going to want to upgrade the entire light system.

[theorchidapartment]

Thanks for that insights! I definitely will be testing it out for a bit to see how well it holds temperature, how much condensation it generates, etc. I think a lot will depend on the ambient temperature and humidity, which change a lot depending on the season.

I could definitely insulate the back, there is a drain, and I just ordered fans for circulation. My plan for now is to put trays of LECA with eggcrate to catch watering runoff.

What would it mean for the compressor to be speed controlled? All I know about this one is that it's a rotary compressor. From the manual I found online, it looks like it's a model from 1994, so it's certainly not the latest technology, haha.

---------- Post added at 10:41 PM ---------- Previous post was at 10:40 PM ----------

Originally Posted by Subrosa

Simply replacing the fluorescent tube isn't going to give you that much more light, as you're limited to using the same wattage tube. You're probably going to want to upgrade the entire light system.

Good to know. I was just looking into taking out the ballast so I can use an LED tube light. Do you have suggestions beyond that?

[Orchidtinkerer]

Love the creativity. Big thumbs up.

I have exactly the opposite problem and can't grow hot growers like Rhynchostylis gigantea, brassavolas and certain Cattleyas. The small ones are no problem but the bigger they get the more space you need to heat/cool.

I have made a box out of 5cm polystyrene for my hot growers and use heaters to heat mine. I can imagine cooling will be trickier than my challenge of heating.

I'll second you need an led grow light not a fluorescent that was used to light ice cream. You can then disconnect the fluorescent.

What type do you want to grow in there that needs the cold? I would have said my favourite would be phal mannii at the moment but I'm sure it could be grown warm like a lot of others that come from colder areas. Neofinetia is a good example. But I have too little experience to know which ones truly need a cold spell vs which ones can tolerate it but don't need one, hard to find out that kind of info sometimes.

[theorchidapartment]

Originally Posted by Orchidtinkerer

What type do you want to grow in there that needs the cold?

Some of the species I have in mind are Sophronitis, Dracula, Masdevallia... a lot of them can tolerate intermediate daytime temperatures (which is what I usually have) but need a cool down at night to survive. I also want to ensure against the occasional blazing hot days and not have to cool the entire apartment just for those orchids.

I actually struggle with hot growers too! I have a Vanda that has bud blasted over and over to show for it, haha. But I don't have room for big showy plants and am intrigued by some of the miniature weirdos, a lot of which come from higher altitudes.

[Draikan]

Is the fluorescent inside the cooled space or outside? It would be best if it were outside so it doesn't put all its heat into the tank.

Do you know what kind of bulb is used? you might be able to find an LED replacement for that size of fluorescent bulb.

If you were able to speed control the compressor, it would let you scale down the cooling power. This would let it cycle on and off less, and run more consistently. This may not matter, but there is some risk of ice forming on the heat exchanger if it's too powerful in your humid environment.

[theorchidapartment]

Originally Posted by Draikan

If you were able to speed control the compressor, it would let you scale down the cooling power.

Oh, that would be great, but if the only control I have is a temperature knob, I'm guessing that's not an option...?

The light fixture is inside the cooler, so I'm looking into replacing it with an LED tube, for temperature and brightness reasons. Gonna do some research about that now. Since the sides are glass, lighting from the outside is also an option, I suppose!

[Orchidtinkerer]

Originally Posted by theorchidapartment

Sophronitis, Dracula, Masdevallia

Ah it's a shame you are not like me, don't really like masdevalia's, find draculas boring and sophronitis is overrated.

A Prosthechea vitellina is a good substitute for a sophronitis

But we each have our own tastes and likes. I can understand the appeal if it is rare where you live but I think they are a bit overrated.

[theorchidapartment]

Originally Posted by Orchidtinkerer

Ah it's a shame you are not like me, don't really like masdevalia's, find draculas boring and sophronitis is overrated.

A Prosthechea vitellina is a good substitute for a sophronitis

But we each have our own tastes and likes. I can understand the appeal if it is rare where you live but I think they are a bit overrated.

Haha, well those were just three genera off the top of my head, but once I can accommodate cool growers, my options will expand greatly! Hope to fill it with all kinds.