The 100Hz is only the theoretical maximum. If you use the automatic frequency setting the pump will detect the best operating frequency itself. Any higher value would cause problems and the pump can't run stable at this frequency so it will stop and start again up to the last frequency which was stable.

In manual mode you can set what you want but you will never be able to go beyond the maximum frequency from the automatic mode since this is the highest frequency which your pump can handle in your loop. Another loop might have a higher or lower maximum frquency. It depends a lot on the restriction in your loop. A higher restriction will lead to a higher frequency.