Not much we can do to help if you don't post your full water parameters...
However, I skimmed through your build thread and didn't see anything about cycling other than adding the rock in. If you do not have a population of nitrifying bacteria (to run your nitrogen cycle), your ammonia levels will always raise to toxic levels.
IMO, if you have zero nitrites and nitrates but a high level of ammonia, your tank did not cycle. All of your livestock are little ammonia factories, and there is essentially nothing in your tank that is removing it other than your water changes which do not seem to be frequent enough to combat the ammonia spikes.