Intestinal Parasite

[Drew0535]

I am very new to fish and I think I might have a sick fish and I wanted to see what others thought. I cycled my tank and added 6 peacock/haps. They were all juveniles and have no color with the exception of the Lithobates has the yellow find and is showing some blue in his head and is probably about an inch bigger than everyone else. Everything was going well and then I added a syno Angelicus and a couple clown loaches that are small this past Wednesday. Everyone has been getting along together well and no issues. Then Saturday I noticed the Lithobates has a long piece of white to opaque feces hanging from him that was longer than his body. It was attached to for about an hour before it finally fell off. From reading what I could find know this usually means intestinal parasites. Sunday when I was looking at him it looked like he may have lost some of his color. The dorsal fin is still yellow but it looks like he might have a little less blue in his face. I am not sure though as he didn’t have much color to begin with, I'm not sure if it is truly a loss of color or me just worrying. He is acting fine and looks like he wants to eat. I have been feeding them NLS sinking pellets and Sunday fed them some peas and that was all. They all went nuts over them except the Lithobates, he tried it and never showed any interest again. Every time I am near the tank he darts to the front of the tank and follows me which he has always done so he appears to be acting normal, no funny swimming or anything. I have read about different medications and was looking into either medicated food or Prazipro. All of the other fish seem fine so I wasn’t sure if I could treat the entire tank with Prazipro or add medicated food and let them all eat it. I do not have a quarantine/hospital tank so I am not sure how I can treat just this one fish. I also have several Anubis nana and java fern so I wasn’t sure if the Prazipro would affect them. I am not too worried about the plants but obviously I would prefer not to lose them if possible. I have been checking my water and no ammonia or nitrites and nitrates have been between 5-10ppm and temp has been between 79-81 since it was set up. I am using the API Master Test kit not the strips. I did do roughly a 30% water change Sunday. Any help or thoughts are appreciated.