Wrong. It will indeed consume yeast and zooplankton, and many other particulates. However, that doesn't mean it gets much if anything from it.
I haven't found any solid evidence that yeast is particularly useful to tridacnids - and to the contrary, Braley (1993) wrote that using yeast to feed larval tridacnids had been only "marginally" better than feeding them nothing at all.
It's also very easy to overdose, which can quickly lead to outbreaks of unwanted algae.
Here's the ref.
Braley, R.D. 1993. Pros and cons of methodologies used in the hatchery and land-based nursery phase of giant clam culture. In: Fitt, W.K. (ed.) Biology and Mariculture of Giant Clams. ACIAR Proceedings No. 47. 154pp.