Good, that's great to hear. so much better than not testing or using strips.0 ammonia and 0 nitrite. Api tests
It cannot hurt, remember there is more in the water than nitrates, it's just that is is much easier to measure and therefore use that as a rule of thumb as to when to change water,I can up that if needed....
you should be able to get away with large water changes daily if necessary, at least till everything looks much better, just build up slowly to reduce stress.