Normal bonsai pots have water perched on top of the bottom of the container after watering.Water drips out of the drainage holes of the pot ( I'm using normal bonsai pots )
So that's three layer below the soil mixture ( pumice , bark & spagnum moss )
I really don't see a problem
You don’t see a problem not because no problem exists but because you have closed your mind to information that contradicts the views you hold. You’re going to do what you’re going to do, however irrational that may be.