The thickness and the pulp from your Blast are related to the types of vegetables that you add in there. Some people like their smoothies a little thicker and helps them feel like they are having something more substantial. However, I can understand why you may not like it.
Try using baby spinach or baby lettuce to reduce the amount of pulp that you are experiencing. You may also consider reducing 25% of your vegetables with the same amount of liquid OR increasing the amount of liquid to thin out the smoothie. Play around with it and have fun Blasting!