Here is what I would do..
after transplanting, water with 7.0 or 7.5 ph'd water and check runoff.. Write down ph'd number and runoff number.
2 weeks later check runoff again. if runoff is lower than 6.0, adjust ph and water on next watering. write down numbers..
And then every 2 weeks later check again.. adjust ph and write down numbers..
and observe your plants..
When you have a list of numbers, you know when to change ph..
If this sounds so complicated and silly.. Just water with 7.0 ph'd water..