Hi all. I did a routine test of my water yesterday and the ammonia was high. I added Seachem Prime (the amount it advises for an ammonia spike). When I tested an hour later, using an API test, the ammonia had fallen to 0.25.

I am aware Prime neutralises ammonia but, considering the test level dropped, is it worthwhile doing a water change today or testing again and then redosing with Prime tomorrow (after 48 hours) if the level is still reading as low?

Test and redose unless it rises again. Also, check nitrite as a nitrite spike may follow on from an ammonia spike.