Depending on what you plan on adding, that may be just fine.
If you want it softer but don't want to buy an RO unit (as cheap as $65), you can buy RO water for like 28-50 cents a gallon, depending on where you buy from. Bring your own container (bucket is ok!) or you may be able to purchase containers there.
Anything else would probably be too tedious and not worth the time or effort.