Orchid leaves going brown

[Miljea]

It's flowering happily on an east facing kitchen windowsill, but the leaves keep going brown.

Watered via a 5 minute dunk every fortnight. Dash of orchid fertiliser as it's in full bloom.

Am I doing something wrong?

That's their growth habit. 3-5 leaves and each time they grow a new one, an old one dies off. In my experience anyway. I kept several alive for a good few years and they all did that.

Thanks! The plant seems perfectly happy otherwise!