Zkittles

I notice after running the air through my water reservoir after adding a ph altering substance that the pH will go back pup closer to what it was before, and what "naturaly" comes out of the tap. I try to use anything I add stuff to right away and wash the water tank and refill it with clean filtered water for next time.To get any remaining chorine to dissipate,and to add oxygen i will turn my air on a few hours before i intend on watering for the day and add my nutrients per 2 gal watering can. and if doing a lot then i wil add it into the whole setup. but that involves more cleaning so i try not to do that.

I think "numbers" might be correct. not PH buffered, could also be something in the medium but its just clay pebbles so hard to mess that up. Easy to test it out. push some of the medium your using into a cup and some nutrients. then measure it a day or two later and track the PH. I have done this on the hour for 8hrs to track my one solutions PH. It did all its swinging within the first 3 hrs then slowed down a lot. Also if you have not done it yet. calibrate your PH probe. Pure RO water can damage probes so always have something in it in terms of fertilizer or dissolved solids. or store it in storage solution. I'm not a huge fan of AN brand. I find it overpriced and not a fan of how they do things. Good Luck!

I assume you are aerating your water and in doing so the amount of CO2 in your air can drastically change pH in water. This could be one issue. Advanced Nutrients is generally a decent nutrient that does not drift much because they load up hydrogen in there to keep it steady. Try mixing a small batch in a bucket, test the pH, let it sit undistrubed and come back in 24hours and test it to see if it drifted without any aeration.