Max tenuifolia is a water hog when it's growing, you can hardly overwater it! Old bulbs that got wrinkled will mostly stay that way, but if you gradually increase the watering you will see that the newer bulbs will plump back up. I also have mine in a mix of bark and sphag, and I'm watering it 2-3 times a week at this time of year. Our conditions are far from being comparable though (60-70% humidity, 75-85F lately), it does give you an idea.
Completely orchid obsessed and loving every minute of it....
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