Thank you for your replies.

I only had them where they could get some sunlight as that is were they were on the edge of the dam. They have sediments from the dam in there as well as some vegetation and a whole variety of insect larvae.
The biggest of them is only about 10mm in the body, then plus the tail.
The fish food flakes are still floating on top, but will get some algae flakes when I'm out later.

Silly question, but what does tadpole poop look like? (lol)