Freshwater Nano Tank Fish

for Small Aquariums

Nano tanks—fully equipped aquariums of five gallons or less—are a fun and popular way to enjoy the beauty of freshwater fish in compact spaces. They fit perfectly on desktops, counters, or shelves and bring a touch of nature anywhere in your home or office.

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Decorative touches such as natural driftwood and live plants—especially hardy species like Anubias and Marimo Moss Balls—make nano aquariums more balanced and visually appealing. These additions help improve water quality and create natural hiding places for small fish and invertebrates.

Only small, peaceful species are suited for nano tanks, and AquariumFish.com offers an excellent variety of fish and invertebrates that thrive in these environments. Choose from tiny gobies, rasboras, tetras, snails, shrimp, and livebearers—all ideal for creating lively miniature ecosystems.

Why Choose a Nano Tank?

  • Compact aquariums that fit anywhere — from desks to dorm rooms
  • Easy to maintain with regular water changes and gentle filtration
  • Low cost of setup and maintenance compared to larger tanks
  • Perfect for showcasing small, peaceful fish and aquatic plants

Popular Nano Tank Fish & Invertebrates

  • Chili Rasbora – tiny, bright red schooling fish
  • Neon Tetra – colorful and peaceful community favorite
  • Pea Puffer (Dwarf Puffer) – curious, personality-packed micro predator
  • Freshwater Goby – active bottom dweller perfect for nano tanks
  • Cherry Shrimp – excellent cleaners that add color and activity
  • Nerite Snails – decorative and great for algae control

Care Tips for Nano Aquariums

  • Use a gentle filter to prevent excessive current for small fish
  • Perform regular 20–30% weekly water changes for stability
  • Avoid overstocking — less is more in a nano tank
  • Provide live plants for oxygen, shade, and aesthetic balance

Explore related collections: Rasboras · Tetras · Freshwater Gobies · Shrimp & Snails · Aquatic Plants

Nano Tank FAQs

What size tank counts as a nano aquarium?
Nano tanks are typically five gallons or smaller, though some aquarists stretch the definition to include tanks up to 10 gallons.
Are nano tanks hard to maintain?
Not at all—just keep up with weekly partial water changes and avoid overfeeding. Stable water quality is the key to success in small tanks.
How many fish can I keep in a nano tank?
A general rule is one inch of fish per gallon, but always consider each species’ adult size and temperament. Many hobbyists keep 3–6 nano fish in a 5-gallon tank.

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