Tap Water-Distilled Water-Filtered Water

[RenettaHogan]

I was wondering if everyone out there uses distilled water when setting up their hydroponics systems? If you use tap or filtered water, what type of changes need to be made when it comes to TDS. I checked my tap water and the TDS level is quite high already. Do I add the TDS nutrient levels to the tap water TDS to get accurate levels of nutrient? For example, if the tap water TDS is 2010, do I add 1700 (nutrient) to that number to get the correct levels of nutrient for the plants? Also, which would be better tap or filtered? I don't always have access to distilled water and am looking for a more user friendly way to help keep my system running efficiently and effectively. I'm quite new at this and want to get it all down correctly before taking it into my classroom. I'd appreciate any info on the matter.