twentyleagues
2500 Club Member
If you actually have .2 ammonia and is not a test error that alone will not hurt your fish. Like @MnFish1 said you have corals that will use it. I would retest that to make sure and keep an eye on it. If it goes up then worry about water changing it. You want phos and nitrate in your tank or you run the risk of getting bad algae water changes will further deplete nitrate.
