Charting with y axis as independent variable

Hi,

First time user,

I'm trying to graph changes in pH in a water column with depth. Obviously it makes more sense if the depth is on the y axis i.e up and down...

Excel automatically makes the x axis the independent variable, is there a way to change this? I can make the graph work my manually entering the series', but with the amount of graphs i need this would take about a lifetime.

Thanks in advance.