not a bad 101, but i'm going to take specific issue with their claims on filter feeding. what i've read contradicts that. T. gigas is known to get a decent chunk of its energy from filter feeding, other clam species, not so much. additionally, it varies highly from species to species. it's a nuanced topic, and i think they over generalized there. i would also disagree that feeding phyto will help clams under 3" of the shell grow. that's an old wive's tale that i don't put much stock in.
there are other giant clams not mentioned. Hippopus sp. comes to mind first. they're starting to make their way in to the hobby more frequently.
high flow introducing bubbles? not really. my primary concern with high flow is annoying the clam or potentially folding the mantle over. again, this varies depending on species. my T. crocea will tolerate much higher flow than my T. derasa.
in response to the byssal organ, not all clams attach the same. for example, in T. derasa the byssal opening will close as the clam matures, and will transition to using their weight, not byssal threads, to hold them in place.
as far as his tips on clam identification, ehhhhh. shell is one piece of identification, i wouldn't put much stock in colors. he specifically points out colors on T. derasa, which can vary. in some cases clam identification is easy, in others it is more art than science. add to that the possibility of them hybridizing, and it can be a fun game.
a long way off from aquaculturing clams? check out Acro Al, he rears several species of giant clam in his driveway.
if you're already successfully keeping SPS, that's a good launching point for keeping clams. it usually means that you have proper lighting, and a good plan for supplying alkalinity and calcium. these guys can suck up a surprising amount of both.
aside from those considerations the most important piece of advice i can offer is learning to identify a healthy specimen. there isn't much you can do in the way of treatment or palliative care. so being able to choose a healthy specimen is a crucial factor for success.
also consider adult size and placement. i picked up my T. derasa in october of 2013, it was so small i could easily hold it in the palm of my hand. in just three short years it has grown probably 4 - 5 times that size, and now sits at about 7" shell length, and can potentially reach three times that size if all goes well. squamosa get fairly large too, maxima and crocea tend to stay much smaller.
depending on the species of clam you choose, placement in tank is important. T. derasa should be in the sand, T. crocea should be high up in the rocks and as close to the light as possible, with other species falling somewhere in between.
oh, and make sure you have a way to cover them if they're close to the surface during water changes. my T. crocea sits a few inches below the water line. so if i do a large water change, it may end up partially out of water. that thing will fire huge blasts of high pressure water up to several feet. soaking me, the floor, the lights, and whatever else happens to be in the way. that can lead to some not-so-fun outcomes if you're not prepared.
