Aquatic plants provide habitat for fish and aquatic insects, and provide oxygen to the water when the sun is out. When there is excessive aquatic plant growth, problems arise as those additional plants consume oxygen during the night and on cloudy days. This can drive oxygen levels down, which could be detrimental to the fish.
Many times, pond owners ask if they can use grass carp to solve their excessive aquatic plant growth problem. The answer is “no,” as they are an illegal species to possess in the state of Michigan, except under a Michigan Department of Natural Resources permit for education or research purposes. This is often confusing to Michigan residents as the neighboring states of Illinois, Indiana and Ohio allow the use of grass carp under certain conditions with the proper permit.