I'm a bit sketchy on using tapwater too, I know it's fine and I've done it myself but really, if you want to be 100% safe, go to a chemist and get some sterile saline solution, you never know what bacteria could be in tap water. That's about it really. The only other thing I want to add is when about actually hitting the vein. I find it best to go in gently first until you can feel the tip of the needle touching the vein, you will feel it, then quickly jabbing in to stop the vein from rolling away. Thanks
I didn't find the right solution from the Internet.