as in a previous copepod post, here is my two cents: My first exposure to the little critters were tiny white flecks in a bowl of water. With a 10x loupe, the parts were recognizable as crustacean. The whole live specimen is plainly visible (and it swims), but you will not have a whole or live organism in the pressurized, and chlorinated water, and the parts should be trapped in the faucet filter screen, as well as white flecks that can come from the disintegration of the plastic dip tube in a gas water heater. Therefor, there is no “berria problem, and not likely a “nosein taam” problem. The yuck factor is actually a good thing, praised in Bava Metzia 62b, and I made a nice living selling filters prior to my aliya. Here, I don’t think it is on the radar, and in the north, they do, or did drink from the Kinneret.
For those that are machmir with microscopic issurim, if you visit the beach, be wary of the sea water, The top 2cm contains plankton, some of which is zooplankton.