The Peaceful Glass Catfish: An Underrated Favorite for Your Aquarium

In today’s blog, we’re discussing the glass catfish, an often overlooked species. It is a highly overlooked fish that used to be very popular back in the ’80s and ’90s. Let’s explore why the glass catfish deserves a comeback. I’m excited to share the species profile of the glass catfish. We have had these guys in our fish room for a very long time, and I love them. Though they were once common, you don’t see them as often today.

That’s why I wanted to talk about them today—because if you come across them in a pet store, they are outstanding fish. They are from Thailand. Most of them are wild-caught these days, but they are not considered to be endangered. The size of these fish usually maxes out right around 3 inches. The fish that you’re seeing here are full-grown. They’re somewhere around four or five years old right now.

The coloration, as you can see—well, that’s what’s so cool about them. They’re basically see-through, and I think that attracts a lot of people because they offer something completely different in your aquarium. Males and females are pretty much the same—generally the same size, same body shape, and same coloration, which means there is none.

One of the standout traits of these fish is their extreme peacefulness. They are some of the most peaceful fish you will ever find. They’re right up there with small rasboras and cory cats. So we’re going to have to keep that in mind as we talk about these fish and how we’re keeping them.

Another cool thing about them is that they are mostly stationary fish, as you’re going to see throughout this video. Though generally stationary, they can burst into extreme speed when feeding or startled. But for the most part, they remain stationary, even though they’re constantly in motion, wiggling around.

Lifespan

Like I mentioned, it’s not unusual to see these fish live for 5-7, even 8 years—maybe longer for some. The ones that you’re looking at here are at least four or five years old.

Cost and Grouping

Another benefit is that they are relatively affordable. When you see them at a pet store, they are usually around $5 or so, which is great because you want to keep them in groups. This helps them feel comfortable. In this aquarium, we have seven. There’s usually a couple that like to hang out on the right side of the aquarium. You see five of them here, but keep them in groups of at least six. That will help them feel more secure.

If there are only one or two of them, they will tend to hide more. Also, if you have aggressive fish in the aquarium, they will hide all the time, become stressed, and probably won’t live very long. So please, when choosing tank mates, think of very peaceful fish.

Tank Mates

Good tank mates include:

• Cory cats
• Rasboras
• Smaller neon-type tetras
• Peaceful barbs like snakeskin barbs, eight-banded barbs, and cherry barbs
• Rainbow fish
• Small geophagus
• Large, peaceful clown loaches
• Small, non-aggressive cichlids like rams, kribensis, nanochromis, and apistos

Avoid aggressive fish, such as:

• African cichlids
• Fin-nipping barbs (like tiger barbs)
• Buenos Aires tetras
• Sharks (red tail sharks, rainbow sharks)

Water Parameters

Caring for them in terms of water parameters is not difficult:

• Temperature: 70-80°F (we keep them at around 78°F)
• pH: Between 6.0 and 8.0 (we keep ours at 8.0 with no issues)
• Water Hardness: Around 4-12 dGH (we keep our GH and KH at around 10 dGH)

It is crucial to have a fully cycled tank—no ammonia, no nitrite. If you don’t know what that means, check out the video in the upper right-hand corner. Nitrate concentrations should be kept below 20 ppm. If they rise above 30 ppm, you may have problems.

Feeding

Some sources claim these fish can be difficult to feed, but I have never found that to be true. I have been keeping these fish since the 1980s. We feed them a wide variety of North Fin foods, including:

• Kelp flakes
• Cichlid flakes
• Community flakes
• Krill flakes
• BugPro
• Live baby brine shrimp
• Frozen brine shrimp

Tank Size

A 29-gallon tank is the minimum size for keeping them in groups of at least six. Though peaceful and calm swimmers, they can move quickly when necessary. Ideally, a 40-breeder tank or a four-foot tank (such as a 55-gallon or 75-gallon) is better.

These fish look amazing in even larger groups of 10, 15, or 20 or more.

Aquarium Setup

This 125-gallon tank is a really nice setup for these fish. They mostly inhabit mid-to-upper water levels, so you’ll want a good amount of open swimming space. However, they also benefit from having some structure, like plants (real or fake), rocks, and wood, to retreat to when startled. These fish startle easily, much like tinfoil barbs or bala sharks, so avoid placing them in busy aquariums.

Substrate

The substrate doesn’t matter, as they don’t interact with it. Choose based on your other fish. We use sand because we also have geophagus and clown loaches.

Even background color doesn’t matter much, but their blue iridescence may stand out more against a darker background. A darker background might also make them feel more comfortable, which can encourage them to be out more often.

Breeding

Breeding these fish in captivity is uncommon. While commercial farms use hormones to breed them, successful breeding in home tanks is rare. Instead, simply enjoy them for their beauty, ease of care, and peaceful nature.

Glass Catfish Care Summary Table

Final Thoughts

Glass catfish are awesome fish. They are easy to care for, live a long time, and look completely different from most other aquarium fish. If you haven’t kept them before or haven’t had them in a long time, give them a try! Just remember:

• Keep them in groups of at least six
• Provide at least a 29-gallon tank
• Choose peaceful tank mates

They are a truly unique addition to any aquarium!