Top 10 Algae Eaters for Planted Aquariums Without Eating Plants
Curated by Kory White · Fractional CRO, CRO SyndicateDirect Answer
The Siamese Algae Eater (Crossocheilus oblongus) is the #1 pick for planted tanks because it actively consumes hair algae, thread algae, and even stubborn black beard algae without touching healthy plants. The Otocinclus catfish is the runner-up, ideal for nano tanks and soft green algae on leaves.
For large tanks with heavy algae loads, the Amano shrimp offers unmatched efficiency and zero plant risk.
How We Ranked These
We evaluated each species on five strict criteria:
- Algae diet specificity — Does it eat only problem algae (hair, spot, BBA) and ignore healthy plant tissue?
- Plant compatibility — Zero reports of nibbling on soft-leaved species like *Anubias*, *Cryptocoryne*, or *Vallisneria*.
- Tank size and bioload — Suitable for standard aquarium volumes (10–75 gallons) without overloading filtration.
- Ease of care — Hardiness in typical planted tank parameters (pH 6.5–7.5, 72–78°F, moderate flow).
- Cost and availability — Readily available at major retailers like Aquarium Co-Op, Buce Plant, or LiveAquaria for under $15 per specimen.
1. Siamese Algae Eater (Crossocheilus oblongus) 🏆 BEST OVERALL
The Siamese Algae Eater (SAE) is the gold standard for planted tanks plagued by hair algae, thread algae, and black beard algae (BBA). Unlike its lookalike the false SAE (*Epalzeorhynchus sp.*), the true *Crossocheilus oblongus* has a clear stripe running through the tail and a black stripe that extends into the caudal fin.
It grows to 5–6 inches, so it needs a 30-gallon tank minimum. Use a group of 3–5 for best results; they are shoaling fish that become timid alone.
In practice, SAEs work best as a cleanup crew after manual removal of large clumps. They will graze on BBA for hours, especially on driftwood and hardscape. They rarely touch Java fern or Anubias, but avoid keeping them with very slow-growing mosses like Christmas moss — they may uproot loose plants while foraging.
At Aquarium Co-Op, SAEs cost $6–9 each, making them affordable for most hobbyists.
2. Otocinclus Catfish (Otocinclus affinis)
The Otocinclus catfish (often called "Otos") is the premier choice for nano planted tanks (10–20 gallons). They specialize in soft green algae and diatoms on broad leaves like Anubias and Amazon sword. Otos are peaceful, stay under 2 inches, and require a group of at least 4–6 to feel secure.
They are sensitive to poor water quality, so only add them to established tanks (6+ months old) with stable parameters.
Use Otos as a maintenance crew for glass and leaf surfaces. They will not touch hair algae or BBA, so pair them with SAEs or Amano shrimp for comprehensive coverage. Feed Repashy Soilent Green or blanched zucchini if algae runs low. At Buce Plant, Otos are $4–6 each; a group of 6 costs under $30.
3. Amano Shrimp (Caridina multidentata)
Amano shrimp are the most voracious algae eaters among invertebrates, consuming hair algae, thread algae, and dead plant matter without harming live leaves. They grow to 2 inches and thrive in tanks 10 gallons or larger. A group of 5–10 can clean a moderately algae-covered 20-gallon tank in a week.
They are fully plant-safe and will not eat Java moss or Riccia fluitans.
Amano shrimp are excellent for high-tech planted tanks with CO2 injection, where hair algae outbreaks are common. They are active during daylight and will graze on driftwood, rocks, and substrate. However, they cannot reproduce in freshwater (larvae need brackish water), so you must buy new stock.
At LiveAquaria, Amano shrimp are $5–8 each; a group of 10 costs around $60.
4. Nerite Snail (Neritina natalensis)
Nerite snails are unmatched for green spot algae and diatoms on glass and hardscape. They come in patterns like zebra, tiger, and olive, and stay under 1 inch. They are 100% plant-safe and will not eat Anubias or Cryptocoryne.
Nerites are ideal for low-tech tanks (no CO2) where spot algae accumulates on slow-growing leaves.
One Nerite per 5 gallons is sufficient. They cannot reproduce in freshwater, so no population explosions. Their eggs (white sesame-seed dots) are unsightly but harmless. Feed Hikari Algae Wafers if algae runs low. At Petco, Nerites cost $3–5 each. For a 20-gallon tank, 4 snails cost under $20.
5. Bristlenose Pleco (Ancistrus cirrhosus) 💎 BEST VALUE
The Bristlenose pleco is the best value for large planted tanks (40+ gallons) with persistent green spot algae and brown algae on glass and driftwood. Unlike common plecos, Bristlenoses stay under 5 inches and rarely uproot plants. They are peaceful and will not eat Vallisneria or Java fern.
Males develop bushy tentacles on the snout.
Use a single Bristlenose in a 40-gallon tank for glass cleaning. They are nocturnal, so supplement with Repashy Morning Wood or cucumber slices. They produce moderate waste, so ensure strong filtration (e.g., Fluval 407). At Aquarium Co-Op, Bristlenose plecos are $12–18 each.
6. Cherry Shrimp (Neocaridina davidi)
Cherry shrimp are the most popular dwarf shrimp for planted tanks, consuming soft green algae, biofilm, and decaying leaves without harming plants. They breed readily in freshwater, making them self-sustaining. A colony of 20–30 in a 10-gallon tank can keep Java moss and subwassertang clean.
Cherry shrimp are best for low-tech tanks with stable water (pH 6.5–7.5, GH 6–8). They will not eat hair algae or BBA, so pair with Amano shrimp. They are sensitive to copper-based medications. At Buce Plant, cherry shrimp are $4–6 each; a 10-pack costs $40–50.
7. Flagfish (Jordanella floridae)
Flagfish are a native US species that eats hair algae and thread algae aggressively, especially in unheated tanks (60–75°F). They stay under 2.5 inches and are plant-safe with Anubias and Java fern, but may nip soft-leaved plants like Hygrophila if underfed. Use them in coldwater planted tanks or outdoor ponds.
Flagfish are best as a temporary cleanup crew for hair algae outbreaks. Remove them after the algae is gone, as they can become territorial. They are hardy and need no heater. At LiveAquaria, flagfish are $6–9 each.
8. Molly (Poecilia sphenops)
Mollies are livebearers that eat hair algae and green spot algae from leaves and glass. They are plant-safe with Vallisneria and Java moss, but may nibble soft Cabomba if hungry. Use a group of 3–5 in a 20-gallon tank.
They prefer hard, alkaline water (pH 7.5–8.5), so they are ideal for African cichlid planted tanks with Anubias and Java fern.
Mollies breed prolifically; keep only males or use as feeders. Feed Hikari Tropical Algae Wafers to supplement. At PetSmart, mollies are $3–5 each.
9. Chinese Algae Eater (Gyrinocheilus aymonieri)
Chinese algae eaters are effective against green spot algae and diatoms, but they become aggressive and may suck the slime coat of flat-bodied fish (like Angelfish) as adults. They grow to 10 inches and need a 55-gallon tank minimum. They are plant-safe only if well-fed — hungry specimens may rasp on Anubias leaves.
Use them only in large, aggressive community tanks with fast-swimming fish like Rainbowfish. Remove them at the first sign of aggression. At LiveAquaria, they cost $5–8 each.
10. Hillstream Loach (Sewellia lineolata)
Hillstream loaches are specialized for diatoms and green spot algae on glass and rocks in high-flow tanks. They stay under 3 inches and are completely plant-safe. They require strong current (e.g., from a Fluval FX4 canister) and high oxygen levels. Use them in river-style planted tanks with Anubias on driftwood.
Hillstream loaches are peaceful and do well in groups of 3–4 in a 30-gallon tank. They will not eat hair algae. Feed Hikari Sinking Wafers if algae is scarce. At Aquarium Co-Op, they are $12–15 each.
FAQ
Q: Will Siamese Algae Eaters eat my Java moss? A: No, SAEs leave Java moss alone. They only target algae on it.
Q: Can I keep Amano shrimp with cherry shrimp? A: Yes, they coexist peacefully. Amano shrimp are larger but not aggressive.
Q: How many Otocinclus do I need for a 10-gallon tank? A: At least 4–6. They are shoaling fish and stress alone.
Q: Do Nerite snails lay eggs in freshwater? A: Yes, but eggs are non-viable and will not hatch. They appear as white dots on glass.
Q: Will Bristlenose plecos eat my plants? A: No, they only eat algae and driftwood. They may suck on soft leaves if starving.
Q: What is the best algae eater for black beard algae? A: Siamese Algae Eater (true *Crossocheilus oblongus*). Amano shrimp are a backup.
Q: Can I use multiple algae eaters together? A: Yes, but avoid overlapping species that compete for the same food. Pair SAEs with Otos for comprehensive coverage.
Q: How often should I feed algae eaters? A: Only if algae is scarce. Feed algae wafers or blanched vegetables 2–3 times per week.
Sources
- Aquarium Co-Op: Siamese Algae Eater
- Buce Plant: Otocinclus Catfish
- LiveAquaria: Amano Shrimp
- Petco: Nerite Snail
- Aquarium Co-Op: Bristlenose Pleco
- Buce Plant: Cherry Shrimp
- LiveAquaria: Flagfish
- PetSmart: Molly Fish
- Aquarium Co-Op: Hillstream Loach
Bottom Line
For a planted aquarium, Siamese Algae Eaters and Amano shrimp are the safest, most effective choices for hair algae and BBA, while Otocinclus and Nerite snails handle green spot algae. Always match the species to your tank size, algae type, and water parameters. Avoid Chinese algae eaters unless you have a large, aggressive setup.
With the right combination, you can maintain a pristine planted tank without sacrificing plant health.
*Top 10 algae eaters for planted aquariums without eating plants: Siamese Algae Eater, Otocinclus, Amano Shrimp, Nerite Snail, Bristlenose Pleco, Cherry Shrimp, Flagfish, Molly, Chinese Algae Eater, Hillstream Loach.*