A method for sensing a fluid depth or a fluid flow of a fluid with a fluid sensing system which includes a sensing element configured to be disposed in said fluid, said sensing element having a positive temperature coefficient of resistance, and said sensing element including a sensing element electric input and a sensing element electric output; a switch including a switch electric input and a switch electric output, said switch being switchable between an open position which prevents electric current from passing from said switch electric input to said switch electric output and a closed position which permits electric current to pass from said switch electric input to said switch electric output; an inductor connected electrically in series between said switch electric output and said sensing element, said inductor including an inductor electric input and inductor electric output; a diode connected electrically in series between said sensing element and said inductor, said diode including a diode electric input and a diode electric output such that said diode electric output is electrically connected between said switch electric output and said inductor electric input; a hysteretic controller configured change said switch between said open position and said closed position; and a means for measuring voltage across said sensing element, said method comprising: i) using said hysteretic controller to close said switch which allows an electric current to flow to said inductor and said sensing element; ii)) after step i), using said hysteretic controller to open said switch when said electric current reaches a upper current threshold (I U); iii) after step ii), recirculating said electric current through said diode to said inductor and said sensing element while said switch is open; iv) after step iii), using said hysteretic controller to close said switch when said step of recirculating said electric current causes said electric current to decay to a lower current threshold (I L); v) repeating step i)-iv) for a predetermined time; vi) prior to step v), using said means for measuring voltage across said sensing element to measure a first voltage across said sensing element when said electric current is one of said lower current threshold (I L) and said upper current threshold (I U); vii) after step v) and after step vi), using said means for measuring voltage across said sensing element to measure a second voltage across said sensing element when said electric current is said one of said lower current threshold (I L) and said upper current threshold (I U), wherein if the first voltage was measured at the lower current threshold (I L), then the second voltage is also measured at the lower current threshold (I L), or if the first voltage was measured at the upper current threshold (I U), then the second voltage is also measured at the upper current threshold (I U); and viii) using said first voltage and said second voltage to characterize said fluid depth or said fluid flow. i) using said hysteretic controller to close said switch which allows an electric current to flow to said inductor and said sensing element; ii)) after step i), using said hysteretic controller to open said switch when said electric current reaches a upper current threshold (I U); iii) after step ii), recirculating said electric current through said diode to said inductor and said sensing element while said switch is open; iv) after step iii), using said hysteretic controller to close said switch when said step of recirculating said electric current causes said electric current to decay to a lower current threshold (I L); v) repeating step i)-iv) for a predetermined time; vi) prior to step v), using said means for measuring voltage across said sensing element to measure a first voltage across said sensing element when said electric current is one of said lower current threshold (I L) and said upper current threshold (I U); vii) after step v) and after step vi), using said means for measuring voltage across said sensing element to measure a second voltage across said sensing element when said electric current is said one of said lower current threshold (I L) and said upper current threshold (I U), wherein if the first voltage was measured at the lower current threshold (I L), then the second voltage is also measured at the lower current threshold (I L), or if the first voltage was measured at the upper current threshold (I U), then the second voltage is also measured at the upper current threshold (I U); and viii) using said first voltage and said second voltage to characterize said fluid depth or said fluid flow.