If you have the valve stem on top (12 o'clock) and a jack under the axle, lifting just enough to take all the weight off the wheel, and you still gave liquid coming out, then I'd let all that liquid out; i.e., drain it down to that point. And then, yes, you can buy liquid/air gauges that don't really look any different than the air gauge, and the price isn't much different either. I think most auto parts stores and places like Tractor Supply Co. have them. Personally, if it were me, and I had calcium in the tires, I'd wash the gauge out a bit with clean water after using it.