Standard weight for a 21" LMB is 5.36 lbs.
With that plumpness it should weigh real close to 6lbs. Great job raising those fish of keeping them growing one pound a year. I think the bass was on its 2nd yr of growth when it was stocked at 6"-10" long, thus I put it in the year class of the 2021 hatchlings. For a northern grown LMB at 6 yrs old and 21" long and close to or at 6 lbs it was growing one pound a year. This is on the low end of the fast growth category for all bass in the USA as noted in my PBoss Mag Mar-Apr 2026 article "Largemouth Bass Talking Points, Two".

Because your are in PA and have shorter growing season days for water above 55F the growth rate of that bass IMO has had exceptional growth rate for more northern waters. Your JOB now is to keep it growing at the rate of one pound a year so in 2030 at 10 years old it will weigh 10 lbs. Always having lots of shiners in the pond will help keep that bass and siblings growing really good. Remember as the pond ages and the carrying capacity laws state, the pond will support only a few of the biggest bass per acre.


aka Pond Doctor & Dr. Perca Read Pond Boss Magazine -
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