pH perfect product- should I add some pH down?

Hi there,
I have an Aerogarden recirculating hydro system. For nutrients I have been using pH Perfect.

The pH level falls to around 6.3 when I feed them and then gradually increases to 7.0 after a few days.
They say not to add any pH down solutions. What do you think?
The plants look healthy it’s just that I’m concerned they are not uptaking the nutrients properly at that high a pH level.

You basically have to ignore (still check them though, to be safe!) pH readings when using the pH Perfect products. It doesn’t actually change your pH (much). What it really does is make all the nutrients and supplements available to your plant regardless of the pH (within reason - it should be between 4 and 8).
So, the gist of it is - your plants should be fine and taking up all the nutrients and supplements.