young society finches dying everyday

Question
I had a cluthc of 5 society finches. They were doing just find and the other day one was sick at the bottom of the cage. Took it to the vet, but he died. The vet told me he would do an autopsy if another died. The next day, another one got sick and died. Then this morning I found the next one. I finally removed the last two. I am not sure if they are getting attacked or what. the vet said it may be viril, and they had no wounds. I dont want to lose the last two. I personally think the dove or canary or another finch is doing them in. We also have zebra finches who started to eat older eggs. Any advise, i would appreciate. After the last dead one, I knew I had to remove the other two. They fly well and eat well and look healthy. Just like the other three before they died. Thanks.

Answer
That sounds horrible. It's hard to tell. I'm going to ask you several questions to see if it's something you're doing (finches die easily). My answer depends in your own so please answer honestly.
1. What kind of food are you feeding your birds? Is it from a reputable pet store or cheap stuff from some guy?
2. Did you buy the birds from a pet store or breeder?
3. Is the food fortified with vitamins and minerals?
4. How old is your food? How is your food stored?
5. Do you change the food in the food dishes once a week?
6. Do you clean the water dish with soap and water everyday?
7. Is the water dish in a place where food, poop, and other contaminants may fall in it?
8. Do you have a cuttle bone or crushed eggs shells in the cage?
9. Do you feed them human food?
10. Do you clean the cage once a month?
11. Is the cage big enough for the amount of birds you have?
12. Do you have enough perches for the birds?
13. Is there enough flying space for the birds?
14. Are the perches cleaned once every two months?
15. Are there nests in the cage?
16. Is the vet suggesting stuff like rice water? (If so, find another vet)
17. Is the vet prescribing a drug called Chloropalm? (If so, find another doctor or see if you can get Baytril)
18. Have you treated the birds with a drug called Ivamech (or Ivomech I'm not sure)?
19. When you hold the birds up to your ear, do you hear clicking?
20. When you feel the birds is there breastbone sticking out like the blade of a knife?
21. Do they sleep often?
22. Does more food end up on the floor instead of in them?
23. Do they sleep on the floor (VERY bad sign)

Sorry, I realize these are a lot of questions but they are important