Amazon Leaf Fish (Monocirrhus polyacanthus) is an advanced-level freshwater fish that needs at least 20 gallons and 75-82°F. A leaf-mimic ambush predator that drifts head-down and snaps up small fish whole. It is shy and slow, so it should be alone or with fish that are too large to eat but too gentle to bully it. Many specimens only accept live food, which is the main reason it suits experienced keepers.
Care facts at a glance
| Scientific name | Monocirrhus polyacanthus |
|---|---|
| Family | Polycentridae |
| Origin | Amazon and Guianas, South America |
| Adult size | 3-4 in |
| Minimum tank | 20 gallons |
| Temperature | 75-82°F |
| pH | 5.0-7.0 |
| Temperament | Ambush predator, eats small fish |
| Social behavior | Solitary |
| Swim level | Mid, drifts like a leaf |
| Difficulty | Advanced |
| Diet | Carnivore: live feeder fish, shrimp, often hard to switch to frozen foods |
| Typical lifespan | 3-5 years |
Quick tips
- Plan on live food; many refuse frozen and dry.
- Keep with calm tankmates too large to swallow.
- Keep the tank dim, planted and softer, with a gentle current.
San Diego water
Prefers softer, more acidic water than San Diego's tap (pH roughly 7.6-8.6, hard). Most keepers blend tap with RO/DI water or use a remineralized RO/DI supply. Learn the numbers in our San Diego tap water guide.
Before you buy
Make sure your tank is cycled (how to cycle a tank), check your numbers with the water testing guide, and use the compatibility guide to check tankmates. These are general ranges; individual fish and local water vary.
Find it at Pet Zone
Pet Zone Tropical Fish is a San Diego aquarium store with two locations. Stock changes daily, so call ahead if you are after a specific species or plant. Shop online at petzonesd.com.
4160 Convoy St, San Diego, CA 92111
(858) 987-0309
Open daily, 10am-6pm
Aquascaping, planted tanks
4266 University Ave, San Diego, CA 92105
(619) 283-1812
Closed Monday; Tue-Fri 10:30am-6pm, Sat 11am-6pm, Sun 11am-4pm
Monster fish, koi