[ReefTECK]

James Fatherree notes that in his research he has found documented cases of relatively small clams eating particles up to 240 micrometers. It is worth contesting that clams could possibly feed upon cyclopeeze which are about 600-800 micrometers, it certainly doesn't hurt to try with a big clam.

Furthermore, when noting the sexual development of gonads a lot more than can be summed up here is available to take into acount. You should do some reading if you want to get a comprehensive idea of what really goes into it.

Although it is worth noting that James Fatherree does note in his book "Giant Clams in the Sea and the Aquarium," (one of the most comprehensive guides to Tridacnids to date); "To sum this up, the data from these papers clearly show that clams of any size more than a couple of millimeters do not need and additional source of carbon when living under ideal environmental conditions."