im just saying that MI zanclus cornutus is technically a carnivore, with a diet of benthic microalgae, sponges, seasquirts, bryozoa. this and the increased daily feeding might tax your existing filtration more than a bunch of herbivores and planktivores, putting more stress on the coral.
in terms of algae, compared to tangs which have built-in knives on them, MI comes bare-handed to the fight.