Best % combination for 0-0-22 Langbeinite with Fox Farm Ocean Forest soil?

Sounds like a great way to burn the shit out of a plant's canopy to me. definitely bump perlite % closer to 50% including whatever comes with it. FFOF is a high-water capacity soil.

FFOF is a hot soil and does not need amending with anything that provides nutrients. Extra perlite is great, more drainage is key. Maybe when they are a bit older you could add in some of the 0-0-22 into a top dress with other things you plan to amend.. or if you're gun hoe on adding it in I would not do more then 0.5% total volume. Eg 1L pot max 5ml/L 25% is way to high for anything that's amending nutrients IMO. Other sources online say 1-2 TBSP per 1Gal of medium for mixing in. 1TBSP=15ml and 1 Gal=3.78L so 15/3.78 = 3.96ml/L or 7.92ml/L for 2TBSP. Not to far off from my suggestion above. granted this is not taking into account the soil your useing is already amended, its suggesting this for depleted soils or soil that need amending and FFOF does not. Not till its nearing depletion aorund week 4ish. Good Luck!