I posted this in the coco section a few days back, so apologies for copy and pasting but I am too tired to write it out again...
These ingredients are taken directly from their labels on their bottles of aqua flakes. Very popular brand which seems to work for quite a few ppl.
Aqua Flakes part A is "Derived from Calcium Nitrate, Ammonium Nitrate, Nitric Acid and Potassium Hydroxide"
Potassium Hydroxide is PH up (also known as caustic soda or Lye)
Part B is "Derived from Nitric Acid, Potassium Hydroxide, Phosphoric Acid, and Magnesium Sulphate
Nitric Acid, Phosphoric acid are both used for PH down, while Potassium hydroxide is a PH up. Both opposite PH affecters being used within the same fertilizer.
By that I would have to guess that having PH up and PH down within the same nutrient tank would have very little negative effect and possibly even have positive effects. After all potassium, nitrogen and phosphorus are all used by the plants and what is left over simply balances each other out.
Again...I have no definitive proof of this but looking at the formula in which both exist, it is hard to see where it would be detrimental to anything. -BB