From what I understand those levels (.18ppm) is harmful to saltwater corals and other inverts not the fish.
An old article on a famous board reported that the at tap copper levels in 3/4's of the cities in the U.S. had copper levels of 250ppm or less.
I think the epa allowable is 1300 or 1100 ro 1000 ppm or so.
A world health origanization studying the copper effects on corals had a paragraph on bioaccumulation of copper by marco algaes. In that study the macros were reported to be exposed to varying levels of copper up to 250ppm. And then the copper was measured in the macro algaes. At 250ppm the macros rose from something like 30ppm to 1020ppm in two weeks. The bioaccumulation was linear to the concentration being used. So half levels in the water meant half levels of copper in the macros. After the two weeks equilibruim had not been reached and the macros were still accumulting more copper.
So yes live plants or in that case macro algae can consume the copper and very heavily.
But for a fish tank it simply is nothing to worry about.
A coral reef tank with delicate corals is another case.
Plus one thing to do is to simply use the cold water faucet and let it run for 30 seconds or so before collecting. That limits the copper in the water.
I go even further by just topping off so I'm not adding copper back into the tank.
My 55g mixed reef tank had a very heavy bioload with numerous "easy" type soft corals for years. Not so good with the few sps type I tried though.