Scat (Ruby and Green) (Scatophagus argus) is an intermediate-level freshwater fish that needs at least 90 gallons and 75-82°F. A round, spotted fish sold young in freshwater, with the ruby form showing red patches. Adults grow larger than many buyers expect and do best in brackish water. They nibble plants, so real plants rarely last.
Care facts at a glance
| Scientific name | Scatophagus argus |
|---|---|
| Family | Scatophagidae |
| Origin | Coastal mangroves, estuaries and river mouths, Indo-Pacific |
| Adult size | 8-12 in |
| Minimum tank | 90 gallons |
| Temperature | 75-82°F |
| pH | 7.5-8.4 |
| Temperament | Peaceful but bold; eats plants and small fish |
| Social behavior | Groups of 3+ in a large tank |
| Swim level | Mid |
| Difficulty | Intermediate |
| Diet | Omnivore: vegetables, algae wafers, pellets, frozen foods |
| Typical lifespan | 8-10 years |
Quick tips
- Move toward brackish water as the fish grows; juveniles tolerate freshwater, adults decline in it.
- Handle with care; the fin spines can sting.
- Plan for a long, spacious tank for the adult size.
San Diego water
Naturally suited to San Diego's hard, alkaline tap water once it is dechlorinated (the city uses chloramine, so use a conditioner that handles it). 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