Vanda with dry roots - watering problems?

[XMaraX]

I'm new to vandas, in fact I bought my first one 2 months ago and kept reasearching what were the best ways to water it properly. I put it in a vase and kept watering it every 4-5 days (like filling the vase and the emptying it after 20-30 minutes).
It looked happy at first but then I noticed that her roots turned brown as if they were dry and had begun to rot. I removed her from the vase and saw that she still had some green roots although most of them are brown ( I cut the rotting ones off as they were quite damaged) and also seems very dry when I touch them. The leaves are in good condition though and the stem is ferm.
I need suggestion with what I should do next.
Help?

Here are some pictures: