In the past week I've lost four drawfs- a blue, two flames and a rainbow. They all died while I was at the tank, three of them just after feeding. The food I'm using has been in use for four months, and is a mixture of spirulina flakes, new balance staple, and bio blend. They all died the same way- they would be normal then all the sudden they'd start swimming in circles really fast then they wouldn't move anymore. I tried moving the last three to another tank as soon as they started, but they still died. I bought at least one of them from a different lfs. Has anyone else experienced anything like this? I still have a flame (1 month old), a blue (1 week), and a rainbow (1 day).