I have standard MS medium, sugar and 7g agar 296 (Phytotech) pH adjusted using 1M NaOH to 5.8.

Works when prepared normally but when I add silver nitrate the medium does not set completely.

Changed the agar to 8g/L and the media resembled concrete.

I tested the final pH of the unset media after autoclaving and it was 4.0 which appears to be the reason why there is no setting.

How do I manage to get agar to set and keep a higher pH to allow for nutrient exchange for the plants? - your thoughts would be appreciated