Just add cocos
Define the water conditions
Get a routine going on adjusted for small plants (low EC) and adjust later to bigger plants (higher EC and more water).
Better to give them a little less then a little more. Ph goes up all the time as they consume fertilizer. When they’re really thirsty you can lower the ph a little more (5,9 - 6), it rises again soon they start consuming their fertilizer.
But adjust ph only in the water, do not try to get your cocos to change ph. Just use it to transport your A and B solution to the plant’
Let the plant adjust to a proper routine and leave it at peace, just make sure it gets enough water with proper drainage.
Keep it simple. Less is more.
Also: ph is never static, plants consume and liquid evaporates. Changing conditions by random events, which are alright as long you keep it steady on a routine in the water.