Learning Objectives

By the end of this lesson, learners will be able to:

• Identify the two main feeder fly species used in dart frog keeping.
• Maintain clean, productive cultures with consistent yields.
• Prevent escapees inside the vivarium and the home.
• Troubleshoot common problems like low production, mites, or weak flies.
• Manage feeding routines that minimise waste and mould.

Lesson Content

Fruit flies (Drosophila melanogaster and Drosophila hydei) are the primary food source for most dart frogs.
Managing them correctly ensures:

• consistent nutrition
• clean vivariums
• stable feeding routines
• stress-free care

Mismanaged cultures can cause:

• mould outbreaks
• inconsistent feeding
• weak or low-nutrient flies
• mite infestations
• flies escaping into the home

This lesson provides a reliable, low-hassle fruit fly system.

1. The Two Main Types of Fruit Flies

(1) Drosophila melanogaster

• Smaller species
• Ideal for Ranitomeya and juveniles
• Faster breeding cycle (10–14 days)
• Better humidity tolerance

(2) Drosophila hydei

• Larger species
• Better for Dendrobates and Ameerega
• Slower breeding cycle (18–25 days)
• Nutrient-dense

Most keepers run both species simultaneously.

2. How to Make Strong Fruit Fly Cultures

A strong culture contains:

• Fresh media
• Ventilated lids (fabric, coffee filters, or mesh)
• Excelsior or coffee stirrers for climbing
• Good humidity
• Stable temperatures (21–25°C)
• Healthy starter flies

Basic Steps:

1. Pour media into the tub (1–2 cm deep).
2. Add water until pudding-like consistency.
3. Add a pinch of yeast on top.
4. Insert excelsior (wood wool) or straws.
5. Add 30–60 flies to start the colony.
6. Cover with lid and date the tub.

Cultures should be replaced every 3–4 weeks to avoid decline.

3. Production Timeline

Melanogaster:

• Day 0 → Setup
• Day 3–4 → Larvae visible
• Day 7–10 → Pupae
• Day 10–14 → Ready to feed

Hydei:

• Day 0 → Setup
• Day 5–7 → Larvae
• Day 10–15 → Pupae
• Day 18–25 → Ready to feed

Running staggered cultures ensures you never run out.

4. Preventing Escapees Inside the Vivarium

Flies escaping into the home is the #1 reason partners ban dart frogs.

To minimise escapes:

A) Feed from a cup, not the tub

• tap flies into a deli cup
• dust them
• feed gently over the feeding station

B) Lightly mist the feeding area first

Wet surfaces trap flies briefly and encourage frogs to eat quickly.

C) Feed smaller amounts

Offer only what frogs eat in 10–15 minutes.

D) Use a feeding leaf/platform

This keeps flies off the glass and substrate.

5. Common Culture Problems & Fixes

Problem 1: Not enough flies

Causes:

• weak starter culture
• too hot or cold
• media too wet/dry

Fix:

• set up new cultures with fresh media
• stabilise room temperature
• use high-quality starter flies

Problem 2: Mites in the culture

Causes:

• humidity too high around culture
• old cultures touching new ones
• contaminated flies

Fix:

• separate cultures
• run mite barriers (petroleum jelly rings)
• keep cultures dry externally
• quarantine new cultures

Problem 3: Cultures moulding

Causes:

• too much moisture
• old media
• poor ventilation

Fix:

• reduce water content slightly
• use vented lids
• move to cooler/drier area

Problem 4: Smelly cultures

Causes:

• bacterial overgrowth
• too many flies in one tub
• expired media

Fix:

• use fresh media
• clean tubs properly
• avoid overcrowding

Problem 5: Weak, slow flies

Causes:

• old culture
• low nutrients
• overpopulation

Fix:

• feed from younger cultures
• increase yeast
• rotate cultures more frequently

6. Keeping Your Feeding Area Clean

Cleanliness reduces algae, mould, and bacterial issues.

Always:

• wipe around the vivarium after feeding
• remove excess flies
• store cultures away from vivariums
• keep lids clean
• replace cultures every 3–4 weeks

Never:

• blow flies into the tank
• shake cultures violently (kills flies)
• keep cultures near direct heat
• store cultures in the vivarium cabinet

Key Takeaways

• Run multiple staggered cultures for consistency.
• Avoid escapees by feeding from a cup and misting lightly.
• Keep cultures at 21–25°C with good ventilation.
• Replace cultures every 3–4 weeks to prevent crashes.
• Fix issues early: mould, mites, weak flies, or poor production.