Dwarf Neon Rainbowfish
Melanotaenia praecox
Also known as Praecox Rainbowfish
Edited by Ivan F. · Reviewed
Beginner verdict
A compact, electric blue rainbowfish with red-edged fins, perfect for a planted community tank. It is very peaceful and suits many small fish, but it can be skittish unless kept in a proper shoal. Keep several and the males will show off their brightest colors daily.
Care at a glance
- Min tank size
- 14 US gal
- Footprint
- 24 x 12 in
- Temperature
- 73–82 °F
- pH
- 6.8–7.5
- Hardness
- 5–15 dGH
- Swim zone
- Mid-Water
- Min group
- 6 fish
- Lifespan
- 3–4 years
Dwarf Neon Rainbowfish care mistakes to avoid
The mistakes beginners most often make with this species.
- Do not buy just one or two. Keep at least 6 fish so they feel secure.
- Keep a real shoal. A few fish stay skittish and rarely display their color.
- Use a lid, because startled rainbowfish can jump.
- Give it open swimming room at the front, even in a heavily planted tank.
- Check your tank before you buy. Our sourced minimum is 14 US gallons.
Dwarf Neon Rainbowfish tank mates and swim zone
Mid-Water
Spends most of its time in this part of the tank.
Poecilia reticulata
Xiphophorus maculatus
Xiphophorus hellerii
Poecilia sphenops
Trichogaster chuna
Trichogaster lalius
Hyphessobrycon amandae
Dwarf Neon Rainbowfish is much larger than Ember Tetra and may frighten or even eat it.
Boraras brigittae
Dwarf Neon Rainbowfish is much larger than Chili Rasbora and may frighten or even eat it.
Danio margaritatus
Dwarf Neon Rainbowfish is much larger than Celestial Pearl Danio and may frighten or even eat it.
Barbodes semifasciolatus
Their temperature ranges barely overlap, so you will have little room for error.
Tanichthys albonubes
Their temperature ranges do not overlap, so one of them would always be stressed.
Carassius auratus
Goldfish suit cooler water and are not suited to tropical tanks, so Dwarf Neon Rainbowfish is a poor match.
Dwarf Neon Rainbowfish feeding and care
How to feed
- Feed quality flakes and small pellets.
- Add live or frozen foods regularly for its strongest color.
- Feed small portions you can see finished within a couple of minutes, because overfeeding fouls the water fast.
Telling males from females
Mature males are larger and brighter than females, with a much deeper body and red-edged fins.
Plants that suit it
Species facts
- Family
- Melanotaeniidae
- Native to
- Mamberamo River, West Papua
- Adult size
- 3.1 in (8 cm)
- Temperament
- Peaceful
- Social needs
- Schooling/Shoaling (6+)
- Diet
- Omnivore
- Water flow
- Moderate
- Substrate
- Any
- Live plants
- Yes - Loves Plants
- Shrimp
- Adult Shrimp Only
- Fin nipping
- None
- Vulnerable to nippers
- No
- Breeding
- Moderate
Dwarf Neon Rainbowfish FAQ
What size tank do Dwarf Neon Rainbowfish need?
Our sourced minimum is 14 US gallons (54 liters), with a footprint of 60 x 30 cm. A bigger tank is always easier to keep stable.
How many Dwarf Neon Rainbowfish should I keep?
Keep at least 6 fish. Bigger groups usually look better and behave more confidently.
What can live with Dwarf Neon Rainbowfish?
Good matches on our list include Fancy Guppy, Platy and Swordtail. Avoid White Cloud Mountain Minnow and Goldfish.
How long do Dwarf Neon Rainbowfish live?
Care guides report about 3–4 years. Stable water and a good diet make the biggest difference.
How can I tell male and female dwarf neon rainbowfish apart?
Males have red or orange edges on their fins and a deeper body. Females have yellow-orange fins and look slimmer and plainer.
Where to buy Dwarf Neon Rainbowfish
We have not found a store that sells Dwarf Neon Rainbowfish under its scientific name yet. We add stores as we confirm them.
Live animals and plants travel by courier. Check the store's live-arrival guarantee, and only buy once your tank has cycled (see how to cycle a fish tank).
Some US states restrict certain species. Check our US state aquarium rules table and your state's own rules before you buy.
Complete the tank
A forgiving setup with room for a small community.
Tank size for this species
At least 14 US gallons (54 L), 60 x 30 cm footprint
Filter
Hang-on-back or large sponge filter
Easy to maintain and strong enough for a community without blasting the fish.
We are still choosing products for this.
Heater
Adjustable heater, about 5 W per gallon: 100 W at 20 gallons, about 150 W at 29
Enough power to hold a stable temperature in most homes. Size up for a cold room.
We are still choosing products for this.
Water Conditioner
Dechlorinator such as Seachem Prime
Tap water contains chlorine or chloramine that harms fish.
Seachem Prime US
Fritz Complete Water Conditioner US
API Betta Water Conditioner US
sera aquatan Spain
Tetra AquaSafe Spain
Maker's page · Sold at Kiwoko · Sold at Tiendanimal · Sold at zooplus.es
Why we chose these (Best Water Conditioner for Betta Fish). Nobody here has used or tested them.
Test Kit
Liquid kit such as API Freshwater Master
Tracks ammonia, nitrite, nitrate and pH while the tank cycles.
API Freshwater Master Test Kit US
API General & Carbonate Hardness Test Kit US
Maker's page · Sold at The Shrimp Farm · Sold at Bulk Reef Supply
sera aqua-test box (Cl) Spain
JBL PROAQUATEST COMBISET Plus NH4 Spain
Why we chose these (Best Test Kit for a Freshwater Aquarium). Nobody here has used or tested them.
Cycle the tank before adding animals. See our guide on how to cycle a fish tank.