an active reef tank with solid purple live rock covered in sponges and worms and the typical dsb can eat up 4-6 ppm in 24 hours to plain zero, tested on salifert and the occasional 1/20000 api ammonia kits
if yours cannot take 1 ppm ammonia and munch it down to zero or darn close, any type of movement, within 24 hours then during your 20 days we've lacked either on the bottle bac or the feed/ammonia portion. I predict it should be able to move some, Id be surprised at that much surface area after 30 days that cannot move it one bit.
if it rapidly closes it out to zero within 24 or better down from just 1 ppm which exceeds all reasonable starting bioloading, after 30 days, that's a done cycle. as mentioned above for nitrite, any weird readings on wastewater wont matter after 30 days if ammonia behaves.
see what you think of that fallow period stuff. as i read it, its the only way to go especially on a large tank. it means that you're stocking everything but fish up front...as soon as you get a balance you can stand to look at for 76 days, then you wait (fallow) that long before adding a single anything other than change water and feed.
fish come in only from quarantine completion, and any frag you ever add, every snail, for the life of the tank, is ran through a fallow phase. its serious business, this disease prevention game regarding fish. glad you didn't use an early one.
in all cycling charts online, nitrite follows what ammonia does at day 30-40 given no aberrant spikes, test misreads (which occur) etc. that's one reason we kick out nitrite readings, and the fact at this chloride level it just doesn't matter. we started with known levels of ammonia that mathematically already determine the known nitrite levels with or without testing confirmation and they're not poisonous at the used levels.