Hi Zach-
Thanks for the great question, and thanks for using the Post and Page Builder for WordPress.
There are two ways you could fix this, depending on your design preference.
First, you could reduce the height of the block with the background using the padding adjustment tool, either on the top or bottom of the row:
Or, you can manually add a CSS rule to prevent the image from tiling, even in large blocks. This will be the most effective way to prevent it, regardless of the image size, but you’ll need to keep in mind that the default background color will be shown where the tiled image was previously. Navigate to Appearance > Customize > CSS/JS Editor and paste this line into your CSS Code field:
.background-parallax { background-repeat: no-repeat; }