Dwarf Neon Rainbowfish (Melanotaenia praecox) is a beginner-level freshwater fish that needs at least 20 gallons and 74-80°F. A small, bright rainbowfish with a blue body and red fins. It is a good fit for medium community tanks, needs a group and open swimming space, and does best in clean, moderately hard water.
Care facts at a glance
| Scientific name | Melanotaenia praecox |
|---|---|
| Family | Melanotaeniidae |
| Origin | Northern New Guinea |
| Adult size | 3 in |
| Minimum tank | 20 gallons |
| Temperature | 74-80°F |
| pH | 6.5-7.8 |
| Temperament | Peaceful, active |
| Social behavior | Schooling, keep 6+ |
| Swim level | Upper to mid |
| Difficulty | Beginner |
| Diet | Omnivore: micro pellets, flakes, frozen foods |
| Typical lifespan | 4-5 years |
Quick tips
- Keep a group of six or more.
- Use a tight lid; rainbowfish jump.
- Feed small portions, twice a day.
San Diego water
Tolerates San Diego's hard, alkaline tap water (pH roughly 7.6-8.6) with slow acclimation and a conditioner that handles chloramine. 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