Magnesium issues and questions

I have another one for you. Since my hydro plants were weeks old I have had problems with pink stems and leaves, with sometimes brown tips. I keep reading it’s probably a magnesium issue. Which I can see because of ph levels. I keep the ph around 5.7 - 5.8. From what I’ve read magnesium absorption requires a PH of 6.0 and higher.

So if most of the nutrients are absorbed at 5.5 to 6.0 especially phosphorus, and I’m in bloom with them so I need to make sure it gets plenty of that. What’s the best way to address this?

What do you do? Do you jack the ph up over 6.0 for a few days then bring it back down?