On those swirls Steph, after talking with some others, I do think the simple swirls were accidental. Apparently if the marble machine gets out of alignment with the tank, the stream drags on one side and causes it to fold, making the simple swirl pattern. With all the machinery moving, the machine can vibrate out of place a little and start making swirls. The operator notices and knocks it back in place again. Whether or not that's what happened with the more involved swirls, I don't know. Just wanted to correct my previous thoughts, don't want to spread bad info.