Is Happy Frog stabilized with lime?

[TheFertilizer]

I was wondering about Happy Frog and why it seems to always have a pH of 7. I have used this batch pretty much through two cycles and it's still hanging around at 7, despite all the nutrients, flushing, so on and so forth.

I was wondering what I could do... Or if I even should... Mix into this much soil to bring the pH down to 6.5?

Side of the tote says 18 gallons