I have been told that Silver Dollars are pretty nippy. At least that was what a LFS told me when I wanted to add some to my angel tank a few years ago.
silver dollars get big dont they? arent they pacus?
No, they are not pacus.
A longtime favorite for community tanks, there is little doubt where this attractive silvery fish got it name. Although Metynnis argenteus is the most commonly encountered of the sub-family of Myleinae, keep your eyes open and you'll no doubt see several other varieties at your local pet shops. I enjoy visiting shops in other towns to see which varieties they have on hand. Look for spotted or even striped specimens, as well as ones with fins of different sizes and shapes. These fish are Charcins, and are sometimes mistaken for Pacus or Piranhas.
Almost every account I've read about Silver Dollars describes how shy they are, in fact manuals often include cautionary remarks about being sure the other fish don't eat the food before the Silver Dollars get to it. However, I've had many Silver Dollars and none of them had any trouble competing for food. They are definitely skittish, and will leap out of the tank if the lid is open and they are startled. I've found that over time they become rather tame, and can even be tame enough to hand feed. One of my favorite Silver dollars even allowed me pet him regularly. In my experience the ones who became tame were single specimens, rather than those kept in schools. Speaking of schools, it is advisable to keep Silver Dollars in small schools of four to five fish whenever possible.
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