I learned years ago about bat guano and pot growing but I never heard about how catfish eat it and then grow larger because of it.
One thing about catfish is that normally most types will grow in relation to the size of the body of water they inhabit. Small ponds equal smaller catfish, very large lakes equal very large catfish. There are written logs of old Mississippi River paddle boat crew members and Captains and passengers reeling in catfish that were allegedly hundreds of pounds while the same species of catfish in small bodies of water never grow to that size. So maybe it is because of the bat guano and maybe it is also because the body of water they catfish live in that goes into the cave is very large.
We used to farm raise catfish in ponds on the land our nursery is on and of course we harvested as often as possible but we stopped a number of years ago now and the remaining catfish have not grown to a much larger size because they have lived for so many more years. Like I said normally they will grow in relation to the size of the body of water they inhabit.
