20 Gallon Low Tech Planted Tank (Setup Breakdown)

By: Billy | March 21, 2024 | Planted Tanks

I’ve wanted to build a 20-gallon planted tank for a while, so I decided to document my journey to help anyone who feels overwhelmed. If you’re just looking for a step-by-step guide on how to set up your tank, check this article.

First things first, below is a summary of my setup.

So, why did I pick a 20-gallon tank?

20-Gallon Tank

My first tank was a Marineland 5-gallon portrait, which I stocked with Neon Tetra. I went to my local chain pet store, and they told me I could stock plenty of Neon Tetra in my 5-gallon, but it ended up being a disaster. This was my fault; I should’ve researched Tetras more.

I noticed them acting aggressively towards each other, which I knew was a sign that something was wrong. I knew I needed a larger tank for them to feel comfortable.

After some research, I went for the UNS 60s 20-gallon aquarium because I wanted space for more fish. This is my second UNS rimless tank, and I love it!

I don’t think I could ever return to an aquarium that isn’t rimless… The look of them is so clean!


I went for the Tidal 55-gallon hang-on-the-back filter (HOB). It’s always a good idea to get a larger filter if you can. I went with the Tidal because I heard a lot of great things about it. I’ve had it installed for over three years and have had no issues. I would gladly buy it again.


There are eight Neon Tetra and twenty cherry shrimp. I picked these with intention because of the colors. The vibrant blue of the Neon Tetra contrasts nicely with the bright red/orange shrimp. They school nicely together, and it’s incredibly calming to watch.

neon tetra


I went with hardy plants since my tank is low-tech (no C02 injection). Starting with the foreground, I used Pearl Weed (Hemianthus Micranthemoides). This isn’t the hardiest plant, but I saw it at my local store, and they said it was easy to grow. However, looking back, I wouldn’t have got it. The roots are so thin that they were easily uprooted when I was trimming.

I then scattered some Anubias Nana throughout the midground. I glued two to the Pacific wood arch and two larger ones at the arch’s base. Anubias are incredibly resilient plants, and I’d recommend them to any beginners. Just don’t give them too much light, as they’re slow-growing and can quickly become covered in algae.

For the background, I used six Java Ferns (Microsorium Pteropus). I tried angling them towards the center to draw attention to the Pacific wood arch. Creating a visually compelling composition is one of the main reasons I love building planted tanks. Java Fern is another hardy plant that is beginner-friendly.

aquarium plants


The light is the Fluval Planted 3.0 (15inch). I decided to stick with Fluval since I’ve had a great experience with their Planted Nano light. You can find cheaper alternatives, but what sold me is their app functionalities.

You can connect to it via Bluetooth on your phone, customize the light levels, and have it automatically turn on. This way, you don’t have to manually turn it on and off daily. It just depends on your budget.

fluval light


I’ve been using Fluval Stratum Substrate in my planted aquariums, and it works well. For this setup, two (8.8lbs) bags were enough. One thing I wish I had known sooner was to make it lower in the front and higher in the back. This gives it a cool aesthetic and adds more depth to your scape.


Pacific wood mixed with small Estes Pagoda Stone. The centerpiece is two Pacific wood mixed to form an arch.

It took me a while to get the placement right. Before you put in any water or plants, I’d recommend laying down your substrate and messing with the composition.

You can change it once it’s filled with water, but it could uproot your plants and detritus.

20 gallon planted tank hardscape


Some issues I ran into and how I solved them.

White Fungus Algae

The first issue was the opaque white fungus/bacteria on the pacific wood. This appeared just a few days after I set up the tank. I would brush it off almost every single day, but it kept coming back. The solution was adding 20 cherry shrimp because they feast on it. It’s nonexistent now.

Pearl Weed Issue

Another challenge I ran into was trimming the pearl weed. The roots are incredibly thin, making it easy to unroot them. I don’t think I would get it again because of this.


I've been building freshwater aquariums with my dad since a young age. A few years ago, I shifted my focus to low-tech planted tanks. My goal is to share my experience to help make yours easier.