Originally we only offered the flat bottom tanks in our line of tanks. Eventually, fit was discovered that they are ideal for growing algae with natural sunlight, however some growers wanted to something a little more. Several customers wanted an easier way to harvest the algae from the growth chambers, particularly the bottom. Siphoning works for the flat bottom tanks, and is a great option for smaller scale operations, however large scale operations wanted an easier option. We were asked if we could make a tank that would be able to drain itself and the idea of a paper cone was tossed around. It was all that simple, we tried other options and in the end, using a paper cone like construction was found to be the best method to produce the bottoms. This method allows us to achieve various angles to fit different diameters and specifications. All it took was a request for easier harvests and soon enough one of our standard tank lines was created.