Persistent 0.25 Ammonia Problem. Need Help Brainstorming.

as the title said I need help brainstorming solutions to my 0.25ppm ammonia reading.
Just tested my water and perameters are
Ph:7.4
Ammonia:0.25ppm
Nitrite:0ppm
Nitrate:25ppm
I’ve been doing daily water changes to get the nitrate down to 15 ppm. Using the API master test kit. Tested facet water and showed
Ph:7.4
Ammonia: 0.25ppm
Nitrite: 0ppm
Nitrate:0ppm
Background on the stock:
2 nerite snails(zerbra)
1 featherfinned catfish to be trasered to a 65 (3.2inches)
2 full grown amano shrimp(got today and love watching. Their antics)
Feeding schedule
Monday:have a cube of mysis shrimp.tuesday:half a cube of beef heart. Wensday: half a cube of spiralina brine shrimp. Thursday: half a cube of bloodworms. Friday: half a cube of emerald entree. Saturday and Sunday: new life spectrum Thera a+ 1mm pellets 7. I know I feed a lot but every morning I check to see if their is any uneaten food and have never seen any left.
Planted with a back wall of moneywort(new and still growing. Crypto weditii, baby amazon sword that I got for free at work(was a new sprout that grew off the main plant)z. 1 anubias nana(medium size) 1 anubias Bartoli( medium size) both Anubis are in the pot still ribsome out of the ground.
Filtration: fluval 106 canister filter. Media: stock corse sponge, fluval biofoam media in bottom tray with seachem matrix stuff on top in the tray. Second tray.seachem matrix on bottom and purigen stuffed on top.
I recently switched filtration from the stock Aqueon filter but it’s been a month and a half so the media should he pretty mature by now. The filter is set to the highest flow rate and creates only a moderate currant.
I dose seachem comprehensive, excel, iron, potassium, and phosphate. Also root tabs for the crypt and amazon swords. Have a 13 watt full spectrum light that is on 6-8 hours a day.
For water changes I use seachem prime. Aquatop 50watt heater set to 77.8-78.3 use a digital thermometer to maintain temperature.
I have an RO/DI water system that I bought for a future saltwater setup and if worse comes to worse I can go full RO/DI and dose the water with seachem equillebrium.
Hoping someon with some experience with ammonia in the tap water can help me by telling me how they resolved their issue with persistent ammonia. And the daily water changes have been about 20%. Just realized I never said what size tank it was. An Aqueon 5 gallon minibow.
Also if I’m doing anything wrong with my setup just tell me any help is appreciated.

 

As per apI the ammonia test has an accuracy of +/- .25. So I would get it tested either with another kit or at a lfs to see if its accurate.

 

I’ll get another ammonia kit on amazon, are their any you recommend?

 

My API kit always reads .25 ppm ammonia. Tap water, filtered, bottled, always the same.
It’s a problem with the kit, wouldn’t worry about it.

 

The biggest bang for your buck is the apI tests. I think they have that margin of error due to the manufacturing process and human error.

 

The biggest bang for your buck is the apI tests. I think they have that margin of error due to the manufacturing process and human error.

The master freshwater test kit is the one I have. I just wanted to see another brand to compare the results to make sure at just an error in the API test. I see seachem has a ammonia test have you heard any good or bad reviews about this test kit?

 

My API kit always reads .25 ppm ammonia. Tap water, filtered, bottled, always the same.
It’s a problem with the kit, wouldn’t worry about it.

Thank you I’m prettty sure it’s actually zero now but I think I’m going to get another brand to test kit to make sure so I can have that piece of mind.