What you need
You can get the plastic on Amazon or you might be able to find it at the hardware store in the painter section. Fold the plastic in half and lay it flat on the ground. Iron the edges with a hot iron but be sure to place parchment paper on the ironing board and on top of the plastic and be careful not to let the iron come in direct contact with the iron. The plastic will melt and stick to the iron.
Leave a 6 inch gap in on of the corners for inserting the hose. When filling the blob be sure to elevate the opening to prevent the water from getting out. Fill the blob until it is almost tight. When it is full tape the opening closed with duct tape. We did find a few leaks where the iron and either missed or melted a hole in the plastic but duct tape did the job to patch any leaks.
*Our experience was slightly different because our hardware store didn’t have 4 mil in the right size so we had to settle for 3.5 mil which I believe made a big difference.
Getting close to full!
Our 2 year old was excited but a little nervous to get all the way on.