The reason why I push back against the advice of needing to feed clams so much, is it sends or gives new hobbyists the wrong idea of their care requirements and creates this false belief that feeding them is more important or necessary than the light and water conditions in which they actually require to thrive. Proper lighting is more important to clams of all sizes and age than what goes into the system/tank. One simply needs to feed their fish enough to produce urea/waste in order to provide enough nitrogen and phosphorus to uptake. Having measurable nutrients should be enough in most cases. Adding phyto should be seen as “feeding” the whole system/tank and adding to the benthic succession process.
I will admit that I’m pretty passionate when it comes to clams and sometimes I come off as being harsh or crass, but I’m simply trying to help others understand their care and needs, because they are such unique animals that can be kept by most with a little effort (and reading). Cheers!