Fishless Cycle Help

When the water buffer is completely gone, the PH can suddenly crash to 5 or 4 or even lower. I have been there. It dropped all the way from 8.0 overnight. If the water becomes too acidic, it will no longer be an ideal environment for the bacteria to grow. The cycle can stall or even go backwards if you know what I mean.

80~160ppm nitrate is insanely high.
The nitrate buildup is too fast to not doing partial water change every day before adding more ammonia.