Please Help Rooster with BAD Diarrhea

I have a rooster with diarrhea that is watery and green. It has been going on for a few weeks....He is eating normal....drinking more water than usual.....has not lost weight and seems fine except for the green watery diarrhea that has a bad odor. I did worm him a long with my other chickens on April 17th with Valbazen because I thought it might be worms because he had not been wormed for some time. I did not see any that were passed after worming. I followed with proboitic and vitimins on April 18th. No others have diarrhea and they were together but I now have him seperated. It is some what explosive when he poops. It did seem today that his poop was a bit less watery. We do not have any vets in our area that treat chickens. I did find a vet that would do a fecal test for worms and coddodia for $16 and a gram stain for bacteria at the cost of $60- $65. He does not treat chickens but he would do the tests. I am wondering what I should do....I do have corid and not sure if I should treat with that/ Any help and info would be great. Thank You!