no that's not a concern in any setting for a marine tank/proceed on
that's likely an nh4 reading which isn't even the marine version of ammonia we reference, we use nh3 in the hobby (10x less than above)
reef tanks don't run zero ammonia, which is why a low trace level is a good sign, not a bad one. corals use that small degree for food along with other materials
this may help to know: after a cycle there's no need to ever test for ammonia in a reef display. the only thing you need to do to control ammonia is make sure no dead fish are wedged in the rocks, simply removing any animals that don't make it ensure your reef tank's ammonia can never be out of spec and you'll never need to test for it again.
testing during a cycle is common, but also optional> we have means to cycle tanks without any testing for ammonia and nitrite. you'd be better off testing calcium and alk, and getting a digital calibrated probe if you want to test pH don't use color guess kits. testing for ammonia is a huge waste of time when it's this predictable in a cycling, or cycled tank.