Hey, it sounds like you’ve got a solid compost tea brew going, but that rising pH is definitely something to keep an eye on. What you’re seeing is pretty common as the microbes become more active during the brewing process, especially with ingredients like fishmix and worm castings, they can release ammonia or other byproducts that cause the pH to drift upward, sometimes as high as 9. That high of a pH can be harmful to your plants, as it can lock out essential nutrients like iron, phosphorus, and manganese. The good news is, you can easily fix this by adjusting the pH after the brew is complete, using something natural like citric acid or a garden-safe pH down solution to bring it back into the optimal range of around 6.2 to 6.8. Also, consider slightly reducing the amount of fishmix or shortening your brew time to 18–24 hours, especially if your ambient temperatures are warm, since longer brews can intensify the pH swing. Just make sure your water is properly dechlorinated beforehand so the microbes aren’t being killed off. With those adjustments, your compost tea should stay much more stable and plant-friendly.
