A Step by Step Guide to Candling your Hatching Eggs

🔦 1. Visual Candling Reference Guide

Use a bright candling light in a dark room and candle quickly (under 30 seconds per egg). The torch on a mobile phone makes an excellent candler, in fact the best I have ever found. Cool and very bright, it's perfect.

✅ Day 0–3

• Egg appears clear.

• Yolk shadow may move slightly.

• No visible veins yet.

✅ Day 4–7

What you should see:

• Spider-like red veins branching outward.

• Small dark embryo spot.

• Clear air cell at blunt end.

Problems to watch for:

• ❌ Completely clear egg (likely infertile).

• ❌ Blood ring (red circle inside shell = early death)

• ❌ An air cell which moves around the egg or is composed of little bubbles. Either of these would indicate a detached or ruptured air cell which makes a successful hatch very unlikely.

✅ Day 8–14

Healthy egg:

• Large dark mass.

• Thick veins.

• Movement when rotated.

• Air cell slowly enlarging.

Concern signs:

• No growth since last candling.

• No visible veins.

• Cloudy contents or odd smell (remove immediately).

✅ Day 15–18

Healthy egg:

• Almost completely dark.

• Large, well-defined air cell.

• Occasional shadow movement.

Stop candling after Day 18 unless necessary.

📋 2. Printable Incubation Checklist

You can copy and print this section.

Before Starting

☐ Incubator cleaned and disinfected

☐ Thermometer calibrated

☐ Hygrometer calibrated

☐ Temperature stable at 99.5°F (37.5°C)

☐ Humidity 30–40%

Days 1–7

☐ Turn eggs 3–5 times daily

☐ Monitor temperature daily

☐ Monitor humidity daily

☐ Candle Day 7

Days 8–14

☐ Continue turning

☐ Maintain humidity 30–40%

☐ Candle Day 14

Days 15–17

☐ Continue turning

☐ Prepare brooder (95°F first week)

Day 18 (Lockdown)

☐ Stop turning

☐ Increase humidity to 35-45%

☐ Do NOT open incubator

Days 19–21

☐ Watch for internal pip

☐ Watch for external pip

☐ Allow chick to hatch naturally

☐ Leave chicks in incubator until dry and fluffy

🛠 3. Common Hatch Problems & Troubleshooting

❌ Egg Not Hatching by Day 22

• Temperature too low during incubation.

• Poor humidity control.

• Late hatch is common if temp averaged slightly low.

❌ Chick Fully Formed but Didn’t Hatch

Often caused by:

• Humidity too low (shrink-wrapping).

• Humidity too high (drowning before internal pip).

• Weak chick from poor egg quality.

❌ Sticky or Wet Chicks

• Humidity too high during early incubation.

❌ Small Air Cell

• Humidity too high early on.

❌ Large Air Cell

• Humidity too low early on.

🌡 Quick Reference Summary

• Temp: 99.5°F (37.5°C)

• Humidity Days 1–17: 30–40%

• Humidity Days 18–21: 35–45%

• Turn eggs: Minimum 3 times daily

• Incubation length: 21 days for chickens and 18 days for quail