I’m on the 38th day of coppersafe treatment for velvet. Only have one trigger left. I changed out 40% of water on the 38th day , yesterday as there was no longer a sign of the parasites. Today it seems there are some parasites on the skin and fish is scraping sand. I can see the spots. The copper level was 2 to 2.5 during treatment period. The water change brought level down to 1.5. Do I need to add coppersafe back to get it back to 2.0 and treat for another week? I’ve hD the Niger trigger for about 6 weeks now. He eats great and is active swimmer I was about to take out more Copper with resin that removes it but it doesn’t appear that the parasites are gone