Thanks, Litzi, you're dead on with the conclusion you have come to! I do feel soooo helpless and sad over this ordeal.
Here is today's update. Still have 6 fish in the Q-tank. Could not find the other half of the "General Cure" by API, so had to buy another box. You treat 1 packet per 10 gallons, so used 5 for first treatment Sunday, then should have treated yesterday ... but couldn't find the rest of the packets ... so treated it second time today. Then wait 48 hours, and do a 25% water change. Active ingredients: 250 mg Metronidazole and 75 mg Praziquantel per packet. Says it is for Gill and Skin Flukes, Swollen Abdomen, Wasting Disease, and Hole-In-The-Head.
So, my plan is to buy at least the highest recommended book, Dave, but in the meantime, until I find the time to locate it and purchase it, I will use the internet to search for clues, once I get somewhat caught up around here. Being gone or busy the last 2.5 weeks has not helped this issue at all. Will buy a microscope, but wondering what magnification I should get.
Tonight I learned that a day or two before I returned from trip to UT and found 5 dead fish, ALL of the fields surrounding my 6 acres was sprayed by airplane with a fungicide. I've been told by local farmer's wife that it would be totally safe for fish, and I would expect it to be, but wondering now if it could have contributed to my troubles. I guess I'm really hooping to find some "reason" for the sickness.
The other thing I thought of, and this may be more likely to be the problem, is that I have turtles that "show up" in my ponds from my farm pond. There is a small one in the ponds right now, was in the koi pond on the weekend, this morning in the goldfish pond, and earlier this summer there was a 7" painted turtles that visited for about a week, back and forth between the ponds. So, now I'm concerned if the turtles are bringing in disease from the farm pond, I see no way to keep them or the bullfrogs out of my ponds, unless I put up a gawdy fence, and completely cover the ponds (frogs would jump over any fence, and not sure the turtles would not scale a fence, too).
So, once again, I am frustrated to not know what is going on, how it happened, trying to think of anything and everything that could have caused it, and 6 fish that are looking pretty sickly, just pretty much "hanging out" in the 55 gal Q-tank. Yes, it's sad, it's frustrating, it's maddening, you name it, those feelings have been around for the last week and a half, and no end in sight ... at least not yet. Still working on it, and will continue to do so until I figure out what caused this, or at least what to do to cure it.
Oh, thought I would let you know no other fish have died since the weekend that I have found or see, so hoping whatever it was is dissipating, if that's possible.