4 Easy Setups for a 20-Gallon Aquarium

You know the saying, “bigger is better”? Well, some of us don’t have the space to keep a huge aquarium or tons of tanks. Keep reading for some creative aquarium setup ideas if you’re constrained to a maximum of 20 gallons like me.

I currently own 3 “nano tanks” – the biggest of which only holds 20 gallons. In my family, my husband Mr. Gamer is a collector of All. Sorts. Of. Things. And I’m more of a minimalist, so I don’t really have the space or even desire to get a larger aquarium right now. However, that means I’ve had to get pretty creative when it comes to optimizing the enjoyment I get from my 20-gallon tank. Like many of you, I get bored with my setups. I want to try new fish, new plants, new equipment… but I’m limited to the same size glass box. So here are four different ideas of what I’ve kept in a 20-gallon tank over the years – the good, the bad, and the ugly!

Tank Setup #1: Community Tank for Beginners

My first setup was a basic community tank inspired by the beautiful aquascapes I saw on Pinterest. It used natural-looking fake plants from PetSmart and black gravel, which was eventually replaced with black sand. For stocking, we've got albino cory catfish as bottom dwellers, neon tetras in the middle, and then marbled hatchetfish up top. The hatchetfish promptly died of ich, which is when I learned the importance of quarantine.

So I replaced them with another top level swimmer, furcatus or forktail rainbowfish. Very lively and entertaining, but I didn’t realize that smaller Pseudomugil rainbowfish tend to have shorter lifespans. The centerpiece fish was a German blue ram, which eventually died because they like hotter temperatures above 80°F. Other centerpiece fish I kept at various times included a honey gourami and a male betta fish, who did surprisingly well in a community tank and actually stopped biting his tail once he had other tankmates to distract him.

This tank crashed because of improper quarantine that introduced a fast-killing disease called columnaris. Awesome. I’ll make an article on treating columnaris in the future, but by the time I figured out what it was, almost everything had died.

Tank Setup #2: Axolotl Aquarium

I seriously wanted to rage quit the hobby at this point. All that time and money poured into this aquarium obsession, and I was left emotionally drained. This is when I left the fish world and took my detour into keeping axolotls. Still kept the same fake plant decor, but had a totally new set of challenges with keeping the water cold and clean enough. After my experiences, I would recommend only keeping one adult axolotl in a 20-gallon tank because of their heavy bioload, and even then, a 20 gallon long aquarium is preferred. But, if you’re looking for an unusual underwater alternative to fish, give axolotls a try because they’re super cool and very derpy.

Tank Setup #3: Planted Tank for Beginners

After my axolotls passed away, I took another long break before starting tank setup #3 – the beginner planted aquarium! The decorations consisted of seiryu stone and spiderwood as the hardscape, as well as easy live aquarium plants like anubias and java fern. No more collectoritis for me – this tank focused on three fish species: a school of albino cory catfish, a school of green neon tetras, and a honey gourami as the centerpiece (plus some amano shrimp as the algae clean-up crew). If you’re looking for fun breeding projects that aren’t livebearers, the cory catfish and honey gouramis were both fairly easy to breed, and I quickly grew the number of fish I owned.

After a year with this setup, I was ready to try something new! Got my first-time experience selling fish and plants at my local club auction, which was really exciting and I was happy to see them go to other hobbyists who will take care of them.

Tank Setup #4: "Shy Guys" Jungle Tank

Today I’m currently on setup #4 with this 20-gallon aquarium – the Shy Guys jungle tank. I’ll go into more detail in future posts on my plant selection and stocking choices, but given my struggles with algae in a tank full of slow-growing plants like anubias, I wanted to try creating a more heavily planted jungle-style aquarium using some faster-growing, beginner plants. I also deliberately chose fish and invertebrates that are all considered super shy (hence the “Shy Guys” theme) because there are certain species I’ve always wanted to try but I heard they hide all the time. So what would happen if I got a whole aquarium of timid creatures? Hmm…

In the future, I have many more plans for this tank. I’d like to do more breeding projects, or perhaps keep some coldwater fish, or maybe once this tank is really established and good at growing plants – try to do a planted axolotl tank? I’m kind of torn since axolotls can live a really long time, so I don’t want to get one until I’ve kept some of my bucket list nano fish… or until I’m able to get another tank. 😉

Question of the Day

Let me know in the comments below what aquarium themes or stocking ideas you would recommend trying in a 20-gallon tank. As always, take time to enjoy your aquariums and I’ll see you in the next post!

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