Purina Game Fish Chow is billed as having at least five different sizes (seven?), and I will vouch for a minimum of five from memory (haven't gotten my first bag yet this year, should show up in four weeks as a birthday present from my wife). They run from about 1/8" up to perhaps 5/16" in diameter and all look identical except for the size.

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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