When it comes to maintaining a thriving aquatic ecosystem, balance is everything. A little bit of algae growth is normal and can even enhance the appearance of a planted tank, but it can easily get out of control.
If you’re looking for a simple way to keep your nano tank clean without having to overhaul your maintenance routine, consider adding nano fish to your freshwater cleanup crew.
In this guide, we’ll explore what nano fish eat algae and provide helpful tips for introducing them into your tank. Keep reading to find out how to choose algae-eating nano fish and what to feed them.
5 Nano Fish that Eat Algae
Many of the algae-eating species that have become popular in the aquarium trade simply don’t work for nano tanks.
They’re either too big for tanks under 30 gallons in volume, too aggressive to cohabitate with smaller fish, or require more swimming space than a nano tank can provide. The solution is to find nano fish that consume algae as part of their natural diet.
If you’re wondering what nano fish eat algae, we’re here to help. Here’s a quick list of some of our top recommendations:
1. Otocinclus Catfish
A smaller, more peaceful alternative to the Plecostomus, Otocinclus catfish are suckermouth catfish with strong algae-eating skills.
There are over 20 species that have been identified, but three remain popular in the aquarium trade: common otocinclus (O. vittatus), dwarf otocinclus (O. macrospilus), and zebra otocinclus (O. cocama).
Otos range from 1.5–2 inches in size and typically exhibit dark brown or gray coloring with white bellies and a black horizontal line running the length of the body.
Otocinclus catfish feed primarily on algae, preferring softer growths like green algae and brown diatoms over green spot algae or beard algae. They’ll also feed on biofilm, so be sure to include some driftwood in your tank.
Otos are a great fit for community tanks and can be kept in schools, as long as there’s enough food to go around.
2. Bristlenose Pleco
Compared to their massive cousins, Common Plecos, Bristlenose Plecos are much better suited to nano tank setups. They can grow up to 6 inches, depending on the species, but may do well as the sole algae eater in a smaller tank.
Bristlenose plecos are easily identified by the bristle-like extensions that grow from their faces, and they come in a range of colors (including albino).
The ideal tank setup for a bristlenose pleco is a well-aerated, planted tank with plenty of hiding places. Like other plecos, these fish are nocturnal and will come out to feed at night.
3. Hillstream Loach
If you’re looking for a truly unique species to add to your nano tank, hillstream loaches are worth considering. With their flattened bodies, horizontal fins, and detailed patterns, they’re incredibly eye-catching.
Many hillstream loaches remain under 3 inches in length, making them small enough for nano tank setups. Some examples include the reticulated hillstream loach (Sewellia lineolata), spotted Borneo sucker (Gastromyzon punctulatus), and yellow-finned hillstream loach (Gastromyzon viriosus).
The key to keeping hillstream loaches happy is high water quality and suitable flow. Hillstream loaches are compatible with other peaceful community species, as long as they can handle faster flow rates.
4. Doctor Fish (Garra rufa)
Famed for their use in “fish pedicure” spas, doctor fish are cyprinids native to the subtropical regions of Western Asia.
They’re naturally found in fast-flowing waters where the water is clear and well-oxygenated. In a captive environment, they’ll thrive in similar conditions. A tank set up to mirror a rocky riverbed or flowing stream would work well.
Doctor fish are omnivores that require a varied diet, but they will feed on algae in the aquarium. If you want to use doctor fish as algae eaters, you’ll need to find the right balance of fish foods that keeps your fish healthy while encouraging them to graze on algae in the tank.
5. Panda Garra (Garra flavatra)
A related species, the panda garra, is easily identified by its alternating dark and light stripes. These fish require mature, cycled aquariums with stable parameters and clean water.
They’ll appreciate strongly flowing water in a tank that provides plenty of places to hide among driftwood, plants, and rocks.
Though panda garras are relatively peaceful by nature, they can become territorial with their own kind. Keep these fish as individuals or in groups of 5 or more to reduce aggression. And be sure to supplement their diet of algae with veggies, algae wafers, and meaty foods.
Tips for Feeding Algae-Eating Nano Fish
While adding algae eaters to your nano tank can help keep problem algae under control, it’s not a magic solution. Proper tank maintenance is still required to keep water quality high and nutrient levels in check.
If you’re running lights in your tank to grow plants, adjusting the timing or intensity may help with excessive algae growth.
Keep in mind that the natural algae growth in your tank might not be enough to sustain algae-eating nano fish.
Some species, like otocinclus, eat more than you may expect. Even if algae is the primary food source for some of your nano fish, you’ll still need to supplement their diet with algae wafers, sinking pellets, and blanched veggies. After all, it takes time for new algae to grow after it’s been eaten.
When feeding algae-eating nano fish, stick to small portions. Start with small feedings once a day or every other day, observing your fish to see how quickly they eat the food and what they leave behind.
You may need to reduce the portions, extend the time between feedings, or simply remove uneaten food before it can break down. It’s better to ensure your fish have a steady supply of food available and have to do a little extra cleaning than to risk them starving for lack of natural algae growth.
Not sure which nano fish are right for your setup? Shrimpy Business can help!
Browse our clean-up crew collection to find algae-eating nano fish suited to your tank, or contact us for personalized guidance and recommendations.