If you can take a sample of your spring water to be tested, like at the grow shop or at an aquarium shop (tell them you are trying to decide if it is feasible to run a saltwater aquarium with your well water), have them check the ppm. If it is very 'soft', you will need calmag. I've killed a crop using spring/well water that pH'd at 7.0 but it was all humic acid and I should have been using calmag. Live and learn! With luck, you live in an area with a limestone substrate and should be just fine.