How to establish living wall on west facing balcony in Brisbane?

[HonoraG]

I am setting up a Living / Green Wall on a balcony in Brisbane near Bunnings Stafford with a western outlook, so shade & late afternoon sun. I have the structure set up plus drip watering system to each pot (see attached image). I am going to use tropical plants for their durability and easy maintenance. My next job is to identify the best medium. As the drip system will be on a timer (set 3 times a day for a few minutes each time), I thought that water retention is important for each pot. From my research, I have identified that a premium soil mix, perlite and vermiculite are necessary for water retention. Some sources say that peat mix and clay balls are also preferred in the combination. I don’t want to go over the top, so just need some pointers from the Bunnings experts. Is premium soil mix, perlite and vermiculite the best medium option? If so, what is the best premium soil mix product suitable for a living wall? Should I include peat mix and/or clay balls in the medium mix? Some clarification about fertilisers when installing the plants in the wall will be helpful, Slow release fertiliser (for continuing fertilisation) and/or a liquid mix when planting? Your advice is very much appreciated.