Best water for my Humidifier?

So I'm growing 2 auto Flowers in a 4"3 and I have a inline fan exhausting out, A little fan inside pushing air around and a humidifier I've read and been told to put RO water in my humidifier and I have been doing that. But it's never pumping enough Humidity out. One day I ran out of RO and decided to put tap in it (I already know it was a bad idea and don't plan to do so again) and my humidifier was pouring out. It raised my humidity to 99% on the same setting it was on while it had RO water and was at a stable 30%. I've also read online you should only use distilled water in a humidifier and should only occasionally use RO water. So basically is their a difference in the amount of humidity produced in different kinds of water? What is the best one to use considering the purity and humidity? Should I just get a different humidifier?