Answer:
The Bible does not specifically tell us what type of fish they were.
I did find in another commentary the following which describes what the fish were probably like:
“Eastern loaves were thin and small, like good-sized crackers, and around the Sea of Galilee, the salting and preserving of small fish was an especial industry. These fish, therefore, were about the size of sardines. The whole supply, therefore, was no more than enough for one hungry boy. But each loaf had to be divided between a thousand, and each fish between twenty-five hundred men.”
Good question, sorry I couldn’t be more specific. I guess you will have to ask Jesus himself someday when you see Him in Heaven. 🙂
Pastor Brad