I have 10 neon tetras right now but recently added 11 more and a few of them started to show up signs of illness. I haven't been able to find a match online but there was large white/greyish patches on some of their bodies, fins a little bit grey on the end, and one looked to have the start of cotton mouth. So I have put them into quarantine and my local fish shop guy (whom I bought the fish off) told me to use white spot cure on them and hat should clear it up, it's not ich but we couldn't figure out what was wrong since they were healthy one day then like this the next.
They were in quarantine for about 2 days before I started medication just to make sure they're alright, and I started just this morning going off what the bottle says, 1mL per 20L of water. It then says to do the same the next day and on the third day do 1mL per 40L.
My question is, do I stop after the third day? It seems like not a very long time for a course of medication but I can't find any info anywhere else. Thank you so much