help cant figure out how to adjust the needle

clip was in the second positon from the top so i moved it down one notch to the middle. seems to have gotten worse so im guessing i should have went to the top position on the needle. question is iwhat happens if that top position gets better but not enough? do they sell other needles for when that happens?
 
You could try going down one jet size and then reset the needle to the 2nd notch from the top and go from there.