Ammonia in copper tank

[Dinodanger]

I have had to add fish to a ht I added cycled marine pure to the tank but I’m having slight ammonia have 4 smallish fish in a 18 Gallon do I add more marine pure or will I always have ammonia even with more media?

 

[WIReefer]

Do you have any media from DT? I would put that in there. Also a water change would be good.

 

[Dinodanger]

Do you have any media from DT? I would put that in there. Also a water change would be good.

I can’t keep doing water changes everyday when ammonia builds and the marine pure is from the display tank