Mine is doing the same. Nearly 4 weeks and no shift in ammonia.
Ph seems to have fallen to high 6s low 7s and ive not got any bicarb and local shops are out of it. Hope it doesnt affecf my already deathly slow cycle too much!
I have no idea whats going on with my cycle.
Ph seems to have dropped to 6.5
Ammonia is at 2 ppm
Nitrite has hit 0 ppm
Nitrate is still 30ppm.
Im thinking about a 95% water change tomorrow and redosing to 5ppm ammonia.
Put in 2 teaspoons of bicarb to raise the pH to 8ish. Since im away for the next 4 days I added 3ml of ammonia to bring the ammonia levels closer to 5ppm just so that the bacteria have something to do.
Again there was no nitrite. Ill check back in on monday evening.