We added food coloring throughout the process so it added to the fun. The kids spent hours out there and had a blast. We will reuse the plastic for its intended purpose as a drop cloth.
To do this yourself all you have to do is pick up a plastic drop cloth (we got ours at Home Depot), fold it in half and ducktape the bejesus out of it to seal the edges. The sealing is the most time consuming but you will be thankful later. We didn't spend enough time on the first run and ended up retaping in spots. The food coloring lasted a few hours but then did fade by the sun. We had a lot of fun pretending there was a shark attack once we added the red. We did visit the sharks earlier today at the Point Defiance Zoo.
here are pics of the kids.