that was an interesting point you brought up. So I looked into it, and it does. My best guess at why they did this was for a flat surface and to install the nuts into the tank. Now with that said, it is minuscule. I filled the tank with water sat it in a frame and let it flow. The original stopped about 3 seconds before the new one. So I'm not that concerned. Also a full tank will last my girl a full day. I don't think she's ever even turned to reserve