Epigeneium nakaharaei yellowing

[Bulbophile]

Ok so, I got this tiny little fella on the 15th of April. And it's small, I think it's kind of a compot, there's like 4 or 5 p~bulbs, very close together. I have it potted in a mix of charcoal, bark, perlite and a little sphagnum. It's housed in my orchidarium. It had one yellow leaf when i got it, but theres another one starting to yellow from the tip down. The humidity is around 70-80%, temps are usually 65-80, water is filtered. Filtered midday light.

Any help would be much appreciated.

~Kevin

PS it's my birthday today!