The tariff is one of the many causes. The Northern industrial states were imposing internal tariffs on the Southern states, to keep them in an inferior competitive position.
How many states identified tariffs as a reason to secede? I think you are w-a-y overstating this matter.
would you happen to know the names of those internal tariffs
Say what? What's an "internal tariff"?
It was more than that. The Northern states had gotten laws passed such as "The Navigation Act of 1817" which made it either illegal or prohibitively expensive to use foreign ships or crew. They then used unfair trading practices, subsidies and monopolies to destroy the Southern shipping and ship building industries, and they then charged extremely high rates (just under the costs of using foreign ships or crew with penalties) to carry the Southern Cargo which created the vast bulk of all US export value to Europe.
According to various sources I have read, virtually all the import shipping from Europe came through New York, where 40% of the profits of Southern produced exports were siphoned off, and then the Federal tariff's were extracted.
The South was paying for 3/4ths of the costs of running the Federal government, and also contributing about 100 million dollars to the New York economy through shipping, insurance, banking and other charges. Roughly 40% of all their profits went to paying these middlemen in New York.
Had the South become independent, the bulk of all trade with North America would have shifted to the Southern ports. It would have cost the North East (and Washington DC) an enormous amount of money.