Though many people do, you shouldn’t simply treat wicks as “one-size-fits-all.” Just because you are getting a burn from the flame doesn’t mean that it’s a healthy flame, or that the wick is the proper size for the candle you have made.
Now, to test whether you have chosen the right wick, you need to consider these three things: • A candle that is tunneling may indicated too small of a wick • A candle whose flame is tall or continuously flickers has too large of a wick • A candle with ½ inch or less of melt, and a standard size flame that’s burning smoothly has the right size wick.
When choosing the right wick for your jar, trial and error come into place. As your candle burns, check the side of the jar and measure how much of the wax has been melted.
Keep an eye on the flame as well, and check to see if it is flickering. Based on the three things you need to watch out for, you can adjust your candle wick accordingly when you make your next set of candles.