10 Best Types Of Fish For 20-gallon Tanks [2025]
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Choosing the best types of fish for 20-gallon tanks can be a daunting task, especially with so many options available and varying care requirements. To simplify your search, we meticulously shortlisted ten ideal fish species that thrive in this size tank, taking into account compatibility, ease of care, and aesthetic appeal. Our curated list is designed to save you time and hassle, ensuring you find the perfect aquatic companions for your home aquarium without the overwhelming research process.
Top 10 Types Of Fish For 20-gallon Tanks In The Market
Types Of Fish For 20-gallon Tanks Review
- Tetra Glass Aquariums are made in the USA and are built to last with scratch resistant glass
- The Tetra Aquarium comes loaded with an LED hood, that provides a natural daytime effect and a Whisper Filter that is whisper quiet while providing powerful, dependable water flow
- Artificial Plants add a unique, natural ocean feel while giving your fish a place to hide which reduces fish stress
- The Tetra Kit includes: one 20 Gallon Glass Aquarium, one LED hood, one Tetra Mini UL Heater, one Tetra Whisper 20 Filter, one artificial Boxwood Plant Mat, four artificial plants. Add gravel and fish to complete your aquarium
- Aquarium Dimensions: 24.2" L x 12.4" W x 16.7" H
- 20 U.S. gallon glass aquarium
- Includes a Marina Slim S20 clip on filter with quick change filter cartridges
- Includes everything you need to get your aquatic home started
- Measures: 24 inches L x 12.5 inches W x 16.5 inches H
- Let the LED light transform your aquarium with each color change. Pause the cycle on any color to fully customize your aquarium
- The anemones sway with your filter current and give your fish a place to hide and relax
- Tetra plants come to life under the glow of Color Fusion LED
- The Tetra ColorFusion Kit includes: one 20 Glass gallon Aquarium, one aquarium hood, one UL Heater, one Tetra Whisper 20 Filter, one Color Fusion Universal Color Changing LED, two Wonderland Plant Multipacks, one Blooming White Anemone
- Aquarium Dimensions:24.2" L x 12.4" W x 16.7" H
- After-sales service - Fish tank belongs to glass products, there will be bumps during transportation. Receive a broken fish tank, please contact customer service in time to return or exchange.
- 100% HIGH-TRANSPARENT GLASS MATERIAL - The fish tank is indeed made of glass after a 3-meter drop and shatter test. If you think it's not, you can try to break it and we'll replace it for free.
- PLANT LIGHTS - 3 types of LED lights provide photosynthesis for plants, providing more oxygen for your aquarium. Reduce adverse reactions of fish caused by lack of oxygen.
- FISH FAVORITE - You can keep bettas, tropical fish, reef fish, guppies, shrimps, crabs, betas and snails in this 20-gallon box, or use it as a fish breeding box.
- WATER TEMPERATURE DETECTION SYSTEM - The fish tank comes with a water temperature detection system, which can help you detect the water temperature and ensure a good living environment for the fish.
- 【MULTIPLE FISH TANK ADAPTATION】This aquarium stand measures 31"L*16.5"W*32.1"H. This 29 gallon aquarium stand is sized to fit 20-29 gallon round, square or rectangular fish tanks, and the bottom can also hold an additional 5-10 gallon fish tank, allowing you to enjoy viewing two types of fish at the same time, increasing the diversity of your home life.
- 【SPACE OPTIMIZING DESIGN】The top displays the fish tank stand, and the bottom can be used for storage or decoration, effectively utilizing the space to meet your pursuit of a neat and personalized home. The bottom padded feet are adjustable and can be adjusted according to your needs.
- 【SUPERIOR WEIGHT-BEARING & DURABILITY】Made of powder coated thick steel and sturdy MDF, the top load-bearing 340lbs and the bottom load-bearing 110lbs ensure the stability and durability of the fish tank stand, so you can use it with peace of mind.
- 【CONVENIENT STORAGE FUNCTION】With a storage cabinet in the center, it is convenient to store fish tank supplies, and the door panel is silent design, which doesn't disturb the fish and keep the fish tank area tidy, meet your needs for home practicality.
- 【MODERN AND STYLISH APPEARANCE】Modern design, simple and atmospheric, suitable for a variety of home decorating styles, enhance the beauty and vitality of the living space, both practical furniture and works of art, add a sense of modernity to your home.
- 【6-in-1 Power Hub (4 AC + 2 USB)】Integrated electrical outlets eliminate the need for a separate power strip. Perfectly powers filters, heaters, lights, and USB devices for your 20-gallon aquarium or reptile habitat
- 【Adjustable & Spacious Storage】Features removable/adjustable shelves to customize space for canister filters, substrates, decorations, fish food, test kits, nets, siphons, and aquarium supplies
- 【Stylish Farmhouse Design & Multi-Functional Use】This aquarium cabinet doubles as farmhouse furniture with its paneling and matte finish, blending naturally into living rooms, kitchens, or home offices. Beyond showcasing your aquarium, it serves as a charming TV stand, kitchen storage cabinet, or display unit for decor – offering versatile home organization without compromising aesthetics
- 【Dual-Purpose Hidden Door】Conceal the power hub and utilize the dedicated storage compartment behind a sleek door. Keep essentials organized and electronics safely hidden for a clean aesthetic
- 【Heavy-Duty & Stable Construction】Engineered for safety with 4x4 wooden legs, a 2.4cm thick engineered wood top, and reinforced industrial metal strips. Supports up to 300 lbs - built strong and stable for your aquarium
- CURVED GLASS AQUARIUM KIT: Includes aquarium, aquarium hood with 2 white & blue LED light sticks, glass canopy, back panel filter, large Tetra Whisper BIO-Bag Filter Cartridge, Bio-Foam, and fish net.
- PERFECT FOR BEGINNERS OR SEASONED HOBBYISTS: Built-in space for filter and heater* housing in the back panel minimizes assembly for a quick, hassle-free installation.
- BIGGER IS BETTER: Our largest 20-gallon tank size means easier water maintenance and improved chemical stability, promoting a balanced aquatic environment for your fish.
- LED LIGHT STICK WITH THREE-WAY SWITCH: Use the toggle switch the choose between White & Blue LEDs on, Magenta LEDs on, Blue LEDs on, and All LEDs off.
- PAIR IT WITH AQUARIUM STAND: Check out the GloFish 20-Gallon Aquarium Stand designed specifically for this aquarium.
- ALL THE EQUIPMENT NEEDED to get started in one box
- LOW PROFILE HOOD contains vibrant cool white LED lighting to bring your aquatic environment to life
- SMARTCLEAN INTERNAL POWER FILTER, providing quick and easy water changes to help improve water quality.
- PRESET HEATER will keep your aquarium temperature at a constant 78 degrees, appropriate for most tropical fish
- KIT INCLUDES: glass aquarium, low profile LED hood, SmartClean internal power filter size medium, EcoRenew filter cartridge size medium, submersible preset heater 50W, premium fish food sample, water conditioner sample, fish net, thermometer and setup guide
- 【MULTIPLE FISH TANK ADAPTATION】This aquarium stand measures 31"L*16.5"W*32.1"H. This 29 gallon aquarium stand is sized to fit 20-29 gallon round, square or rectangular fish tanks, and the bottom can also hold an additional 5-10 gallon fish tank, allowing you to enjoy viewing two types of fish at the same time, increasing the diversity of your home life.
- 【SPACE OPTIMIZING DESIGN】The top displays the fish tank stand, and the bottom can be used for storage or decoration, effectively utilizing the space to meet your pursuit of a neat and personalized home. The bottom padded feet are adjustable and can be adjusted according to your needs.
- 【SUPERIOR WEIGHT-BEARING & DURABILITY】Made of powder coated thick steel and sturdy MDF, the top load-bearing 340lbs and the bottom load-bearing 110lbs ensure the stability and durability of the fish tank stand, so you can use it with peace of mind.
- 【CONVENIENT STORAGE FUNCTION】With a storage cabinet in the center, it is convenient to store fish tank supplies, and the door panel is silent design, which doesn't disturb the fish and keep the fish tank area tidy, meet your needs for home practicality.
- 【MODERN AND STYLISH APPEARANCE】Modern design, simple and atmospheric, suitable for a variety of home decorating styles, enhance the beauty and vitality of the living space, both practical furniture and works of art, add a sense of modernity to your home.
Our Review Process
To ensure you get reliable product recommendations, we follow a detailed review methodology that includes:
- Market Research: Scanning best-selling and trending products in this category.
- User Feedback: Reviewing customer reviews, star ratings, and complaints.
- Hands-On Testing: Trying select products ourselves when feasible.
- Feature Comparison: Evaluating specs, durability, pricing, and safety.
- Expert Opinions: Consulting with niche experts or credible reviewers.
We independently select the top 10 options based on value, quality, and usability. To learn more, visit our detailed review process.
Key Considerations Before Buying Fish for a 20-Gallon Tank
1. Tank Size and Fish Size
When setting up a 20-gallon tank, it’s essential to choose fish that can comfortably thrive in the available space. Larger fish require more room to swim and grow, while smaller species may feel cramped in a smaller environment. Ensure that the adult size of the fish you choose is compatible with the tank’s dimensions.
2. Compatibility of Fish Species
Not all fish species get along well together. Before purchasing, research the temperament and social behavior of potential fish. Some species are territorial or aggressive, while others are peaceful. Mixing incompatible fish can lead to stress, aggression, and even fatalities in the tank.
3. Water Conditions
Different fish have varying requirements for water parameters such as pH, temperature, and hardness. It’s crucial to select fish that can thrive under the same water conditions. Perform regular tests for these factors and choose species that have similar needs to maintain a stable environment.
4. Filtration and Maintenance
A 20-gallon tank requires adequate filtration to maintain water quality. Some fish produce more waste than others, which can affect the tank’s cleanliness. Consider how often you are willing to perform maintenance and choose fish accordingly. Low-maintenance species might be more suitable if you have a busy lifestyle.
5. Stocking Levels
Overstocking a tank can lead to poor water quality and stressed fish. As a general rule, aim for one inch of fish per gallon of water, though this can vary based on the species and tank setup. Plan your stocking levels carefully to ensure a healthy and balanced aquarium.
6. Aquascaping and Environment
The layout of your tank—including plants, rocks, and hiding spots—can influence the fish you choose. Some species prefer dense vegetation or caves for hiding, while others thrive in open swimming spaces. Consider how the tank’s design will support the needs and behaviors of your fish.
7. Feeding Habits
Fish species have different dietary requirements. Some are herbivores, while others are carnivores or omnivores. Ensure you can provide appropriate food for the species you select. Additionally, consider the feeding frequency and types of food available for your chosen fish.
8. Lifespan and Commitment
Fish can have varied lifespans, ranging from a few years to several decades. Be prepared for the long-term commitment of caring for your fish and providing a stable environment throughout their lives. Research the expected lifespan of the species you are considering to ensure you are ready for the journey.
FAQs
What types of fish are suitable for a 20-gallon tank?
Some suitable fish for a 20-gallon tank include small species such as guppies, neon tetras, bettas, and platies. You can also consider dwarf cichlids like Apistogramma or smaller catfish like Corydoras. It’s important to research compatibility and choose fish that will thrive in a community setting.
Can I keep a betta fish in a 20-gallon tank?
Yes, a betta fish can thrive in a 20-gallon tank. In fact, a larger tank is beneficial as it provides more space for swimming and helps maintain stable water conditions. Just be cautious about tank mates, as bettas can be aggressive towards other fish with long fins or similar colors.
How many fish can I put in a 20-gallon tank?
A general guideline is to allow one inch of fish per gallon of water, but this can vary based on the species and their behavior. For a 20-gallon tank, you could typically house around 10-15 small fish, depending on their adult size and compatibility. Always monitor water quality and fish health to avoid overcrowding.
Are there any fish that should not be kept in a 20-gallon tank?
Yes, larger fish such as goldfish, oscars, or larger cichlids are not suitable for a 20-gallon tank due to their size and space requirements. Additionally, fast-swimming species or those that require more swimming space may also not thrive in a smaller tank.
What are some peaceful community fish for a 20-gallon tank?
Peaceful community fish that do well in a 20-gallon tank include guppies, neon tetras, danios, and harlequin rasboras. These species are generally non-aggressive and can coexist with other small fish, making them ideal for community setups.
Can I mix freshwater and saltwater fish in a 20-gallon tank?
No, freshwater and saltwater fish cannot be mixed in the same tank. They have different water chemistry requirements and would not survive in an incompatible environment. It’s essential to choose either a freshwater or saltwater setup for your 20-gallon tank.
What plants are suitable for a 20-gallon fish tank?
Plants such as Java fern, Anubias, and Amazon swords are great choices for a 20-gallon tank. They provide hiding spaces for fish, help improve water quality, and enhance the overall aesthetics of the aquarium. Make sure to choose plants compatible with your fish species and lighting conditions.
How often should I change the water in a 20-gallon tank?
It’s recommended to change 10-15% of the water weekly or 20-25% bi-weekly in a 20-gallon tank. Regular water changes help maintain water quality by removing toxins and replenishing minerals. Always check the water parameters before and after changes.
The Bottom Line
In conclusion, selecting the right fish for a 20-gallon tank is essential for creating a vibrant and harmonious aquatic environment. The ten species highlighted in this article have been carefully chosen based on factors such as compatibility, size, temperament, and care requirements. Each of these fish not only complements the limited space of a 20-gallon aquarium but also brings a unique beauty and personality that can enhance your aquatic display. By understanding the specific needs and behaviors of these fish, hobbyists can build a thriving community tank that is both visually appealing and ecologically balanced.
By following our curated list of the best types of fish for 20-gallon tanks, you can ensure that you make informed decisions that promote the well-being of your aquatic inhabitants. Whether you are a seasoned aquarist or a beginner just starting out, adhering to these recommendations will help you avoid common pitfalls, such as overstocking or incompatibility issues. With the right choices, your 20-gallon tank can become a beautiful sanctuary that brings joy to both you and your fish for years to come.
