Tiny Fish for Tiny Tanks

In a typical Fishkeeper store, you’ll find a huge variety of fishes. With such a kaleidoscope of colour and choice it’s easy to overlook some of the most incredible miniature wonders. For too long, small or ‘nano’ aquaria have been seen as starter tanks for kids, or homes for goldfish – which are far too big and messy for them. Goldfish are hardy and have a long history as pets but it is a bit like trying to keep a horse in your lounge. Save yourself a lot of mucking-out and discover the world of nano fish.


Starting where many parents do, let’s look at a some options for unheated aquaria. As you can’t train a fish to hop out when it needs to use the bathroom, tanks without filters usually run into problems with pollution and these filters are dependent on the bacteria that live in them to process the waste that otherwise poisons the fish. New set ups therefore need to be running before any livestock is added and we’d suggest adding a starter culture of the right friendly bacteria https://www.fishkeeper.co.uk/microbe-lift-nite-out-ii. You’ll find plenty of guidance for first time fish keepers on our website, so we’ll assume from this point on that your aquarium is ready for stocking.



Our recommendation for beginners would be the White Cloud Mountain minnow(Tanichthys albonubes) a small and colourful species that’s also available in a gold colour form. Provided with a reasonable current and some plant cover, a small group will give hours of entertainment as the males compete to impress the females.



For something a little different, consider the perfect choice for planted nano tanks - brightly coloured crustaceans such as Crystal bee shrimps (Caridina cantonensis) are bred in a wide range of colours and always fascinating to watch.


If temperatures are likely to be lower, the Cherry shrimp (Neocaridina heteropoda) are an even hardier option. As they tolerate a wide range of temperatures, these shrimps can also be housed alongside appropriately sized tropical fish. Just make sure that oxygen levels remain high.



One of the fishes that caused quite a stir when it was introduced to the hobby, the exquisite Celestial pearl danio (Danio margaritatus) is a stunning fish and the closer you look the better they get. Males can be a little feisty with one another, so a well-planted aquarium gives them the opportunity to avoid too much conflict.



Adding a heater increases the range of choices available and there’s a wide range of tiny tropicals to tempt you. As small tanks have a limited carrying capacity, strongly shoaling species might not be the best choice if overstocking is to be avoided.


Rainbowfishes are deservedly popular community fish but tend to be on the large side. Luckily the small species known as Blue eyes provide some good choices and of these, the Forktail rainbow (Pseudomugil furcatus) is the most commonly seen.



Well-planted aquaria provide lots of hiding places and this suits shy species like the Sparkling gourami (Trichopsis pumila), which tend to lurk close to the cover they provide. To duplicate their swampy native home, they’ll appreciate the addition of leaf litter such as Catappa leaves, which will add the tannins that stain the water and bring out the best in their colours.



Livebearers can often be rather boisterous for very small tanks but the diminutive Endler’s guppy (Poecilia wingei) is a nicely compact form. They breed prolifically, so it’s well worth searching out a posh form that will be in greater demand should you need to rehome any at a later date to keep the population under control.



Although many of the commonly-seen tetras are surprisingly large or too social for very small aquaria, Ember tetras (Hyphessobrycon amandae) are a tiny species and eminently suitable. Their adult size makes a small shoal a realistic proposition and they really do glow when settled in a planted tank against a backdrop of green foliage. https://www.fishkeeper.co.uk/help-and-advice/freshwater/characins/ember-tetra-



Pygmy pufferfish (Carinotetraodon travancoricus) are an oddball option that combine cute looks with sociopathic tendencies and are best appreciated in the splendid isolation of a species set up. Although they’re small, they do like to be in groups and the males can be a bit territorial. As with many fish, out of sight is out of mind and generous planting can help to minimize friction.



These are just a small selection of options and the chances are that every member of staff you speak to in our stores may well suggest a personal favourite that I’ve not mentioned. With so many species to choose from, it’s safe to say that the perfect choice is waiting for you but with such tiny fishes, you may have to look twice to make sure you’ve not walked past it.

Member of OATA

The Ornamental Aquatic Trade Association