So you have 40% bu’s biodynamic potting soil for a base. Then if I’m understanding you correctly you are going to put 40% coco coir and 20% EWC?
Ok, so I just saw you’re mixing up 2 x 5 gallon fabric pots. depending on how big you are going to grow your plants, I might opt for bigger pots.
You really aren’t going to need very many amendments. Buy a box of kelp, alfalfa, if you can get some basalt or glacial rock dust I would definitely add that. A little calphos aka rock phosphate wouldn’t hurt.
Edit: sorry, I’m really high, it’s late… if you’re adding coco coir, that has a lot of potassium in it already. I would be especially careful with protekt, langbeinite, etc. You may not need any added potassium - at least not till a little later in flower.