The state biologist really did not say the opposite when he said
... but the state biologist said the opposite. He said that the clear water allows deeper sunlight penetration and therefore more water with habitat and oxygen.
What the biologist said was true but more habitat and oxygen does not mean that more fish food is present compared to more fertile water (greenish). More fertile water & more productivity means more fish food per unit of water as in enriched cloudy with a greenish hue from lots of microorganisms present (productivity), usually phytoplankton. The amount of productivity is on a scale or range from essentially none (clear swimming pool) to hyper eutrophic pea (soup green).
What he was saying is with clearer water, it produces deeper oxygen causing more space for fish to live because the oxygenated water layer is deeper but not necessarily more is food present. There is more volume/space for fish to live. What good is more volume or space if production of food is lacking due to lower concentration of nutrients (phytoplankton) that grow the fish food? More space can provide more benthic organisms but not necessarily more phytoplankton-rotifers to feed fish fry. If fish fry do not grow larger, high numbers of fry won't survive to eat the larger foods. Generally the clearer the water is,, the fewer or less food items that are present. Lack of food present results in fewer fish that can survive and flourish (carrying capacity) per acre. Productivity or fertility is measured by how much algae/zooplankton/macroinvertebrates are present in each unit volume (milliliter, ounce, quart, gallon) of water.
