You have done one of the most classic mistake in a start up situation. You have add both autotrophic nitrification bacteria ( Dr. TIM'S One and Only ) and heterotrophic bacteria - probably with a organic carbon source too ( MicroBacter7)- the later will compete out the nitrification bacteria very fast. The other mistake was to add a huge amount of microbacter 7 - you get an uncontrolled growth of heterotropic bacteria that probable deplete all oxygen in the aquarium. One and only can´t be overdosed but microbacter 7 can - that you have shown in a very drastic way.
I would advise you to restart the whole thing - 100 % WC and cleaning everything especially the sand. After that restart your system with a fish and
ONLY Dr Tims One and Only as additive -
please read this for more information about a proper start of an aquarium with fish.
I do not see it as inhuman - no human will be hurt
I think you mean infishan
Jokes aside - I do not see a start with a fish as ammonia releaser to be cruel in any way if it is done the proper way - IMO it is the best way of starting a saltwater aquarium. Please see the article I referred
to above
Sincerely Lasse