The big idea behind small aquariums...Looking into a tiny, yet impactful world.

Part of the art of "being me" is that I love to take some feedback from our community, both in terms of practices and ideas for blogs. The inspiration for today's topic came from a few of you, but was really triggered by an exchange with a member of our community, Nancy Marks, who felt that this would be a really cool topic to play with.

She's right!

And of course, the idea of "nanos" has to start with the sort of "origin story", if you will.  And you KNWO it will be filled with MY "angle" on the whole thing... :) 

One of the interesting developments in the past decade or so is the rise of so-called "nano" aquariums. You know, smaller aquariums, which (oh, and THIS is a debatable aspect) fall into the 2 to 8 gallon (7.57-30.28 L) range or so. 

Now, let's be perfectly honest, it's not like someone "invented" the concept of a 2.5 gallon tank a few years back and this became a "thing." We've had small tanks as long as aquarists were keeping fishes. I distinctly remember using 2.5 gallon tanks when I was a teenager keeping killifish...I remember reading about them in my Dad's vintage late 1950's/early 1960's aquarium books. This is not new. However, it's only in the last decade or two (or so it seems) that the "nano" moniker rose to popularity.

My biased (LOL) opinion about the origin of the serious "nano trend" (Is it a "trend", or simply another hobby "path" to take? That's a good discussion topic, too!) is that this new fascination arose our of the reef aquarium side.

"Seriously, Fellman...You think EVERY recent hobby innovation arose from the reef side!"


Well, maybe. Kinda.. Umm...Okay, well many innovations DC pumps, LED lighting, etc...All this happened while the FW side sort of just "bubbled" for a while, so...yeah...

Anyways, I read on.

There was a certain "early 2000's" audacity that decided to rebel against the rising popularity of larger reef tanks. In other words, I think that the "nano" idea had it's roots in reefers wanting to "give the bird" to the mainstream reef hobby and take the reef aquarium to a more extreme end. "Let's take something that's new and possibly difficult and make it even more challenging...just because!" And of course, we love to give a name to everything in this game- and "nano" made commercial sense.

And of course, the Industry got a whiff of this and smelled the metaphorical "blood in the water" (i.e., MONEY!), and soon a few manufacturers were offering "nano aquariums" for reefs! Usually, these consisted of a tank with some form of integrated, yet undersized filter, adapted light system, and little else. Not really optimum equipment for a successful long-term "reef aquarium", but it was a start, right?


During this time, a lot of people made a lot of mistakes as they pushed the limits of what you could do in a tiny volume of saltwater...a new skill for reef people, but stuff that the freshwater crowd knew how to deal with for a generation...Of course, one of the things reefers do well is take a simple concept and beat the living crap out of it, adding complexity and technology with the goal of making life easier. So, you saw all sorts of oversized, adapted gear mated to these tiny tanks in order to make them work in a better manner...


Eventually, seeing the rising popularity and the arrival of the "DIY" reef crowd, who started tweaking these little tanks with a litany of pricy pumps, reactors, and other accessories, manufacturers decided to move beyond the "21st Century Goldfish Bowl" deathtraps that many nano reefs became, and brought some real tech to the game, with dedicated, properly-sized pumps, filters, protein skimmers, etc. Suddenly, the "nano" became a serious alternative to a full-size reef tank.

And of course, the freshwater crowd was on board long before, working quietly and effectively with them. There may not have been a sexy label attached, but the concept was well-trodden and proven for some time.

Okay, this exhausting, somewhat opinionated "origin story" stuff now over, I think we can all see that the idea of small aquariums for keeping our fishes in a serious manner is nothing "new", but the idea of "seriously equipped" small aquariums for these types of efforts is something that evolved. Kind of like the first "SUVs" in the auto industry. The concept was around for a while, but the actual "category" didn't really take root for many years...until consumer "needs" sort of "justified" them.

With smaller aquariums comes the same level of responsibility and attention as we find with larger ones, right? In fact, one could successfully argue that, due to their smaller water volumes, "nano" are less forgiving and require more attention to basic aquarium practices and husbandry. I mean, if stuff can go south fast in a 40 gallon breeder, shit gets REAL serious REALLY fast in a 2.5 gallon tank, right?


All the "doom and gloom" warnings aside, the idea of nano tanks is wonderful. Besides making the hobby more accessible to people who need to "get a taste" of it without the full blown "mid-size" tank (despite how we feel about it), nano allow the serious hobbyist (hey, that's US!) to use it as a "testbed" of sorts for new ideas, concepts, etc. You could even try a few tanks at once (budget permitting) to test different concepts simultaneously.

Proof of concept work!

And of course, keeping small tanks has a certain "je ne sais quoi" about it, huh?

With our botanical-style blackwater tanks, nano can give us a feel for some of the more exotic concepts, such as deep botanical bottoms and leaf litter beds, "dense matrix" wood assemblages, mud and alternative  substrates, ultra-low pH regimens, etc., etc. Concepts which  might prove even more difficult, risky, and expensive in a larger tank. I mean, with a small tank, you could conceivably come up with an idea, decide to go for it, go to the LFS and purchase it, set it up, and observe it in the same amount of time that it takes you to binge watch a few episodes of "Game of Thrones", or whatever inane drivel is trending on TV these days...

Yup. Easy.

Establishing small tanks is a bit less challenging, in my opinion, because of the smaller size. You can utilize "pre-colonized" bacterial filtration media (filter sponges, etc.) or even "bacteria in a bottle" products, pre-aged wood and substrate, water, etc. Sure, every aquarium needs to establish it's nitrogen cycle, but use of these materials in a smaller system can greatly speed up this process, in my experience. You can't avoid it, but you can help it along. And frankly, you wouldn't want to, right?


Now, the impact on water chemistry caused by botanicals is obviously going to be more significant in smaller water volumes. It will likely take less to accomplish the same thing you might in a larger aquarium. Testing, going slowly, and observing are the keys to success in nanos. And that's kind of a cool collateral benefit of working with nano aquariums: They necessitate careful application of basic aquarium skills, and help us hone these skills, all of which are applicable to a larger aquarium.

And there is that whole idea of "nano fishes", right? Not that these fishes were "bred" or whatever for small tanks, but this is a category of animals which, because of their small size, habits, vulnerability, etc., would be utterly lost in a larger tank, so the "nano" is a great way to showcase them and learn from them!

And of course, it's completely possible to pour large amounts of time, money, and other resources into a tiny aquarium. I know many hobbyists who have spent tons of time and money on this little tanks that would put some of the "mid-size to large" tanks I've kept in years past to shame!  And the concepts that can be more readily executed in smaller tanks is remarkable.

The whole "concept to completion" thing.

There is a certain delight many take in working on these small tanks that can't be overlooked.

This little gallop is just sort of an opening salvo on a topical area that seems to be continuously expanding, and of interest to many in the hobby...In future episodes, we'll discuss more of the art and science of working with these little tanks, some "nuts-and-bolts" stuff, and even some ideas for creating specialized, blackwater/brackish-water, botanical-style aquariums with them.

Interested? Stay tuned.

In the mean time, we'd love to see and hear about some of your nano-tank experiments and ideas. Remember, inspiration is "open source", and everyone's experience is welcome, adding to the "body of work" that is our hobby niche!


Stay creative. Stay smart. Stay focused...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

Scott Fellman
Scott Fellman


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