Ammonia won't go below 0.02 on established tank

[Geoff 282]

Hi I set up a new nan reef tank in Jan 2019 I rinsed the sand for a few hours filled the tank and sump with water from the reef shop added 12 kg of of rock. Then 1 bottol of colony to start the cycle. Since then I have added 2 small clown fish 2 small damsal 1 goby one bleney som coral a rew hermit crabs and two sales nemmis 

 

I change water 30 Ltr per week all fish and corals are looking fine but no mater what I do my ammonia won't go below 0.02 I small feed every other day. All other readings are fine. Stuck for answers

[Christopher Marks]

Welcome to the community @Geoff 282!

 

May I ask what company makes your Ammonia test kit? Some test kits have been found to falsely show a little ammonia when there actually is none.