Come to think of it, I have a friend who even used to BURY his heaters under the gravel. This was in a FW tank, so don't know what this would do under sand, in a SW. Think it would hamper the heat transfer, or heat up the substrate too much, harming the live sand? Or, think it might affect the heater's temp. reading, screwing up when it goes off and on? On first thought, it sounded kind of cool (once again, minimizing how much equipment you see).