As long as you have the prime to bind the ammonia every single day at the same time of day. I don’t go over 24 hours before I add again. What I found directly from the seachem site:So I really don’t need a filter or air stone of any kind in the hospital tank?
Prime® will bind up those compounds for up to 48 hours. If they are still present after that time frame, they are released back into the water, unless Prime® is re-dosed accordingly. Also, if your ammonia or nitrite levels are increasing within a 24-hour period, Prime® can be re-dosed every 48 hours.