10 Best Algae Eaters for Your Freshwater Aquarium
Algae — it’s inevitable in every aquarium. While some algae is harmless (and even natural), excessive buildup can cloud water, suffocate plants, and make your tank unsightly. That’s where algae eaters come in. This guide covers the 10 best algae-eating fish, shrimp, and snails for freshwater tanks — including what makes them effective and how to care for them.
1. Amano Shrimp
These hard-working shrimp are famous for devouring hair algae, green dust, and leftover food. They thrive in planted tanks and are peaceful community members.
- Minimum Tank Size: 10 gallons
- Best For: Hair algae, leftover food
- Tip: Keep in groups of 5+; they need established tanks
2. Nerite Snails
Nerite snails are efficient glass and surface cleaners. They don’t reproduce in freshwater and come in stunning shell patterns like zebra and tiger.
- Minimum Tank Size: 5 gallons
- Best For: Green spot algae, diatoms
- Tip: Secure lids — they’re escape artists
3. Otocinclus Catfish
Small and peaceful, Otos are great for planted nano tanks. They work in groups and love algae films on leaves and glass.
- Minimum Tank Size: 10 gallons
- Best For: Brown algae, soft green algae
- Tip: Keep in groups of 4+ and feed algae wafers when algae is gone
4. Siamese Algae Eater
One of the few species that eats stubborn black beard algae. They are active swimmers and good tankmates for medium-sized community tanks.
- Minimum Tank Size: 20–30 gallons
- Best For: Black beard algae, hair algae
- Tip: Avoid the false Siamese — look for clear black stripe
5. Bristlenose Pleco
Smaller than common plecos, they clean driftwood, glass, and substrate. Hardy and low-maintenance.
- Minimum Tank Size: 30 gallons
- Best For: Glass, driftwood, general algae
- Tip: Provide hiding spots and sinking foods
6. Mystery Snails
These decorative snails help clean plant leaves and tank glass. They’re peaceful and come in bright colors.
- Minimum Tank Size: 5–10 gallons
- Best For: Light algae cleanup, aesthetics
- Tip: Add calcium to water for strong shells
7. American Flagfish
A colorful killifish known for nibbling on hair and thread algae. Best in semi-aggressive or single-species setups.
- Minimum Tank Size: 20 gallons
- Best For: Hair algae
- Tip: Avoid pairing with long-finned species
8. Rubber Lip Pleco
Another smaller pleco, excellent for algae without the size of a common pleco. Peaceful and low-maintenance.
- Minimum Tank Size: 30 gallons
- Best For: Green algae, glass, driftwood
- Tip: Needs high oxygen levels and clean water
9. Cherry Shrimp
These vibrant shrimp are great for small tanks and light algae duty. They also add color and activity to nano setups.
- Minimum Tank Size: 5 gallons
- Best For: Biofilm, light algae
- Tip: Provide moss and fine-leaf plants for grazing
10. Mollies
While not a traditional algae eater, mollies often pick at algae, especially in brackish tanks. Plus, they’re colorful and easy to breed.
- Minimum Tank Size: 20 gallons
- Best For: Surface algae, general grazing
- Tip: Can tolerate brackish water and breed readily
Tips for Choosing the Right Algae Eater
- Match species with your tank size and fish temperament.
- Don’t overcrowd — many algae eaters need group space or territory.
- Supplement with algae wafers or blanched veggies when algae is low.
- Monitor compatibility with plants and tank mates.
Final Thoughts
Algae control starts with good tank habits — but the right cleanup crew can make a huge difference. Whether you go with shrimp, snails, catfish, or a combination, these species bring balance and beauty to your aquarium. Just remember: algae eaters support your maintenance routine — they don’t replace it!
Explore care guides for each species in our Algae Eater Library and subscribe for more expert aquarium tips.
