How to fix accidentally low ph?

My plants have been taken care of for about two weeks by a friend. He grows but for whatever reason does not ph anything. Out of respect for me he agreed to ph while watering my plants and I told him to ph to 6.5.

Here is the problem...He did ph but wasnt sure and ph'd the water before adding the nutrients instead of after. It ended up with my plants receiving a nutrient water mix of about 5.1 ph for two weeks. Obviously way too low. I havent noticed any signs of damage or stress to the plants but am a little concerned. What should I do to fix this mistake?

I was thinking just start back up asap with the correct ph and everything should be fine but some added advice would be very appreciated. Thanks in advance for all your help.

did you put lime in your soil mix? because that would have been the fix, it stabalizes the ph over time and acts as a buffer for the low ph nutes

restart... yields will be crap