Bonsai soil help

hello people,
im having a hard time finding a trustworthy recipe for bonsai mix in new Zealand.
I have river sand ,perlite ,zeolite ,pumice decorative pebbles (daltons), Daltons premium potting mix and garden loam. peat moss too.
What would be a good ratio blend for deciduous trees and natives , I would realty appreciate your input.
Next to pot up are a a Hazel, a Corokia and a Buxus.
I just repot my 60 year old Chinese juniper in :
10% garden loam
20% Daltons premium potting mix
10% peat moss
15% perlite
15% zeolite
30% sand , ( 60% drainage ,40% organic matter) too much organic?)
its seeming to start greening up. This was my first bonsai repot and I put it off year after year due to unfounded apprehension and no available mix. .So, after 7 years in the same container it went kinda yellowish and had a lot of brown dead foliage to remove but looks like its not stressing ;a week later .

Now i'm a little worried it might not drain fast enough. After a week drying out i put 1 3/4 litres of water on it.It takes thirty seconds to drain the flooded surface after each application. Surely that'l be ok .?

please help me .you??

I have no clue but am fascinated with bonsai and want to start one or more in my classroom next term so hope to follow this thread with interest.
I hope you get lots of posts.

Oh boy, I share your pain. I inherited a bonsai'd ginkgo from my Grandmother who had started it in an orange skin from seed over 40 years ago now - so it is a treasure. I repot it every couple of years at mid winter and use whatever potting mix I have with some slow release ferts, and each time I wait anxiously to see if I have killed it this time. So far it has survived my cack handed complete novice efforts and even put on the odd new branch - which of course I am far too terrified to prune or shape beyond the odd bit of very timid wiring. It has a personality now, I call it the sleeping dragon, though it is I believe root over rock and still dozing (I hope!) after this past winter's torturing. I'm hoping to see the faintest hint of green on the old leaf buds any day.

Meantime I bite my nails and wait.

Some drainage is good but you don't have to go overboard. The size of the pot has more influence on the grown (size) of the tree. Feed / water as required is the more important factor as what it can drink /eat and survive on is limited by the reservoir of nutriments available to the "tree" in a small container.

That's the principle I have adopted, treat the tree like any other while understanding it has limited access to resources.

And I'm pleased to confirm, the ginkgo has green, lol. No guilt this year.