# What is tunneling and how do I fix it?

> unneling is when the wick burns straight down the center of a candle without creating a full   melt pool   within 2 hours of being lit Tunneling is typically a

Source: https://support.candlescience.com/en_us/what-is-tunneling-and-how-do-i-fix-it-rJniDBAe

Last updated: 2026-05-01T14:24:44.726Z

Tunneling is when the wick burns straight down the center of a candle without creating a full [melt pool](https://support.candlescience.com/en_us/what-is-a-melt-pool-BJvFEQWRZl) within the appropriate amount of time. Tunneling is typically an indication that the wick is not large enough for your wax, container, fragrance, dye combination but it's possible for a wick that's too powerful to also burn down before it can reach a full melt pool. Depending on how much wax you have left on the sides of your container, you may need to test up or down one or even two sizes in the wick series you are using. For example: if you used the CD 16 with the 464 soy wax in an 8 oz tin and saw tunneling, you would next want to test the CD 18 or CD 16, depending on your burn test results.

![A lit candle in a glass jar with a warm orange glow. The wick's melt pool is small and not reaching the edges of the container.](https://cdn.kustomerhostedcontent.com/media/6945d68a600cd242f80712ea/001e107d76add9c443c37c4032be5a4f.png)

  

For help selecting the right wick size, check out our [Wick Guide](https://www.candlescience.com/learning/wick-guide/) as well as our article on [Choosing the Right Wick Size](https://www.candlescience.com/learning/choosing-the-right-wick-size/).

Our guide on [How to Conduct a Burn Test](https://www.candlescience.com/learning/how-to-conduct-a-burn-test/ ""How") and our [Tutorial Video: Choosing the Right Wick Size](https://www.candlescience.com/learning/choosing-the-right-wick-size/) will also be useful as you test different wicks!