Is there a general treatment for a flock of chickens if two have diarrhea?

[astuemky]

We introduced 3 new chickens to our flock 2 months ago, so now have 6. All are 1-4 years old. Since then one or two of them has had almost constant diarrhea. I can’t figure out which one. Recently one has become more lethargic and stopped laying. Is there any sort of general gentle treatment you can give an entire flock that won’t hurt the ones that aren’t sick? I don’t think it’s coccidea based on no blood that I can tell. But I’m also not able to take them to a vet for identification, so needs to be something I can get from Murdoch’s or online. Like I wondered if giving them the medical fees you can buy there might help. Thanks for any advice.

 

[Rose Quartz]

Medicated feed is for cocci. If that's not the problem it wont help at all.

 

[Eggcessive]

If coccidiosis were a problem, they would need Corid in their water 2 tsp per gallon of water for 5-7 days. Medicated feed would not treat an outbreak. I would also think about worming them with Valbazen 1/2 ml orally and repeated in 10 days. Or use SafeGuard liquid goat wormer or horse past 1/4 ml per pound given orally for 5 consecutive days.