The two suckers may eat a little algae and do a little bottom roiling to help make a little turbidity to the water (aeration mixing) to help reduce algae growth. I've caught white suckers 22"-24" long. IMO white suckers would be better algae eaters than koi or carp because the suckers will not successful spawn while koi, carp and goldfish regularly produce offspring.
http://www.lakesuperiorstreams.org/understanding/whitesucker.html

Last edited by Bill Cody; 09/09/13 08:45 PM.
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