I am an owner of ten rabbits at the moment. At the beginning of the year, I had twelve rabbits and two guinea pigs. First to die was one of my guinea pigs. I found him dead in his cage. Two months later, one of my rabbits passed away too. I thought it was just a coincidence. Only three days after he passed, another of my rabbits died as well. Tonight, a little over two weeks later,my other guinea pig also died. So some information about what I know… I found both guinea pigs dead in their cages, and one’s igloo had been knocked to the side by him. Both appeared to have just dropped dead. The rabbits,however, would be acting entirely fine and suddenly fall ill. They’re eating,drinking, pooping just fine prior. One of my rabbits was even playing with my guinea pig(also deceased) minutes prior to falling ill. The rabbits died pretty fast, within a half hour. The veterinarian did an autopsy on my second rabbit that died, as she was concerned since so many of my animals were dying. She found that Speedy(the rabbit) had passed away from bacterial sepsis. The vet treated all of my pets with an antibiotic to kill the bacteria, so I thought all was well.The vet said it was too difficult to determine the cause but to monitor their behavior. I’ve kept their cages clean, especially after losing so many so suddenly.. But there have been gnat like bugs in their cages that I can’t rid of. I clean their cages and the next day, the bugs are back. I’ve even mixed dish soap and apple cider vineger to attract them away from the cages but it didn’t help at all. Before the two rabbits passed, I had gone on a trip so when I came home(a week later), there were mushrooms growing in two cages. One was in the cage of the first rabbit to pass. I cleaned the cages well since and haven’t seen any mushrooms since. We did have a fly infestation in our house(the rabbits are indoors) when the two rabbits died, but since have not seen many at all. I have been feeding them from bales of Stanlee timothy hay purchased at local feed store. The vet recommended that I toss out the bale I had been feeding them,in case the hay was tainted. For the past two weeks, I fed them hay purchased from a local rabbit rescue. I noticed right away that they hay didn’t feel as sticky or dirty. It also didn’t stay green for days on end like Stanlee. The hay purchased from the rescue went from green to brown within a day or so, and the rabbits ate it right up(they dont like Stanlee). The rescue will be closed for two weeks though, and I couldn’t find any feed stores with hay that wasn’t Stanlee,so yesterday I had to switch back. Then I found my guinea pig dead today. Another concern, though I don’t know how lilely, was that my rabbits have been drinking tap water. I switched them to purified water tonight. All of my animals that passed away were one year old, except for one guinea pig who was a few years old. I’m going back to the vet tomorrow, but I am so panicked and am hoping to get some insight from other rabbit owners. Thank you!