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Orchid Terrarium DIY [An Unusual Fish Tank Transformation]

Here is my orchid terrarium DIY project made from a 20-gallon fish tank. It will be going through some changes soon.

Orchid Terrarium

I actually started out with orchid plants in self-watering planters but thought a terrarium would be fun to build. Orchid Plant Unboxing And Potting Up – Hydroponic Orchids

I have been growing nepenthes pitcher plants in glass tanks for years. They are similar to orchids in a lot of ways.

So my first thought was to just place my orchids inside a fish tank on top of a gravel base.

Fish Tank DIY Orchid Terrarium

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The evaporation helps provide additional humidity. My house can really have low humidity, especially during the heating season.

But what happened was my 20-gallon fish tank was a bit too small to set all 6 pots inside flat. So one was partly propped up to fit.

But then I thought they could all fit do well in a terrarium and look much more natural than sitting around in pots.

Orchid Terrarium DIY

So I will be building a DIY terrarium for my orchids. Here is a view from the top.


It won’t look like this for long but I am going to need to buy some stuff to transform my fish tank into a DIY terrarium.

Setting Up My Orchid Terrarium

Even though I have done this before I always like to do research to get a fresh perspective.

I read a fairly comprehensive article on setting up a terrarium for orchids here.

The writer was well informed but it was not the approach I wanted to take. They recommended leaving the orchids in their pots.

But my whole reason for creating an orchid terrarium was to create a more natural growing environment and not just hide the pots with decorations.

So I ordered some sphagnum moss to hold my plants. I plan on adding more substrate to the tank first of all.

The water level will be kept close to the surface of the stones and plants will then be placed on top without their pots.

I will be using the sphagnum moss around the plants and their roots will be grown in it.

This should provide good airflow around the roots and provide the roots with humidity.

I think the orchids will begin producing more aerial roots as they grow. They will be able to dry out naturally in the air above the moss.

I think this should provide an environment where my orchids will flourish.

I may add a small fan inside to provide some additional airflow if it is needed. I’m not sure yet if I will add driftwood or other ornaments.

So now comes the hard part. Waiting for my sphagnum moss to arrive. So stay tuned.

The Advantage Of Building A Terrarium

A terrarium allows you to create a specialized environment for your plants. My house has fairly low humidity.

While I can’t get my whole house to have the proper humidity for orchids I can do it in a smaller space within my larger space.

I have not added sphagnum moss to my terrarium yet. But after just a few days in my repurposed fish tank, I think my plants look happier and healthier.

Sphagnum Moss On The Way

So my sphagnum moss was ordered online and will arrive today. Meanwhile, my orchids were removed from their self-watering pots.


So I poured a mixture of grow stones and LECA pebbles inside my terrarium and set my plants into this mix.

This layer is about 3.5 to 4 inches thick and the plants are set into it and are slightly mounded above the water level.

When the moss arrives it will be spread around the plants.

I want the moss to make contact with the water so it stays moist and provides humidity.

But I also want to make sure that it is not so thick or tightly packed that it cuts off airflow.

I will be bottom watering my terrarium and if everything works well the moss will wick up water and the roots will have good humidity and also good airflow.

Orchid Terrarium DIY Adding Sphagnum Moss

So my sphagnum moss finally arrived. There were a lot of products available on Amazon.

Some apparently had a lot of trash mixed in with the moss according to the reviews.

Eventually, I found this brand which had good reviews from people who actually used it to grow orchids.

It turned out to be very clean and of high quality. It was tightly compressed and I only needed to use 1/2 of the brick.

If you need sphagnum moss for your orchids I recommend this brand you can buy it on Amazon here.

sphagnum moss

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So the process of turning a spare 20-gallon fish tank into an Orchid Terrarium DIY project went very well. My orchids are doing fine but the tank will help provide some extra humidity.

So my sphagnum moss arrived and after a good soaking, it was placed around my orchids.

This terrarium is made from a 20-gallon fish tank. There are 3-4 inches of LECA and grow stones in the bottom with a water level about an inch below the orchids.

My plan is to have the moss wick moisture up and help provide humidity for my orchids, but I did not want to have too much moss around the roots as the plants grow they should be able to send aerial roots up above it.

SO HERE ARE A FEW PICTURES OF MY ORCHID TERRARIUM

MY ORCHID TERRARIUM

MY ORCHID TERRARIUM DIY PROJECT

MY DIY ORCHID TERRARIUM

Read more: My Tolumnia Orchid Has A Flower Spike

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