MANY OTHER TYPES OF FISH OF EXCELLENT EATING QUALITY HAVE MUCH LOWER FEED AND WATER QUALITY REQUIREMENTS THAN DO CATFISH, AND REQUIRE MUCH LOWER LEVELS OF CAPITAL AND MANAGEMENT. CATFISH DO NOT UTILIZE FEED EFFICIENTLY WHEN THE WATER TEMPERATURE IS BELOW 60 DEGREES F., AND THE TOTAL NUTRIENTS AVAILABLE IN THE POND ARE UNDER-UTILIZED. TROUT, HOWEVER, PERFORM WELL WHEN THE WATER TEMPERATURE IS BELOW 60 DEGREES F. BAIT MINNOWS CAN BE UTILIZED SUCCESSFULLY TO CAPTURE EXCESS FOOD SUPPLY IN THE POND WHEN CATFISH FINGERLINGS ARE SMALL. THEN, AS THE CATFISH BECOME LARGER, THEY CONSUME THE BAIT MINNOWS, THUS UTILIZING THOSE EXCESS NUTRIENTS CAPTURED EARLY IN THE PRODUCTION PERIOD. COMMON CARP, CONSIDERED A TRASH FISH IN THE UNITED STATES, HAVE LOW-LEVEL CAPITAL AND MANAGEMENT REQUIREMENTS. RESEARCH CAN LEAD TO NEW COMBINATIONS FOR POLYCULTURE SYSTEMS WHICH WILL UTILIZE EACH NICHE IN THE FOOD CHAIN AND RETURN OUTPUT TO INPUT RATIOS UNTHINKABLE AT THE PRESENT TIME.