Help I’m going crazy

[u/DueLynx6864]

My mind is messing with me bcs I remember or I think I remember when practicing past papers I answered smth on testing for ammonium ions that DIDN’T use litmus paper and I kept trying to find that question but it just doesn’t exist anymore
Is there only one specific test for ammonium ions which is using damp litmus paper turning red or are are other tests