An alternative way to estimate feed amounts might be to track how long a container lasts someone for a given tank and number of fish. Not something I think that much about, when I get low I buy more, but I'm sure some people would know. Some years ago I did my own fairly thorough version of a feed study, but my objective was to distinguish which products were better, not exact amounts per fish, etc.
Was a mod with Larry Johnson on an African cichlid forum for a few years and he said the same thing, especially aulonocara species being smaller in the wild. (Larry has been diving the lake for years on various research, conservation, and collecting trips.)
I think it depends on the type, though, and not a 100% rule. Some wild species can be just as big or some individuals bigger than most tank counterparts; even so, the wild versions may be slower growing and smaller at the same age.
Imo, wild fish of some types being smaller than tank fish isn't a huge issue in itself, a wild fish is likely expending more energy for less nutrient dense food, but that same fact argues for feeding less-- a wild fish expends more energy, often for less nutrient dense foods, so our fish often don't require as much some think.
But imo there's likely another factor, which is what's in some foods. Humans are statistically getting fatter and there's a lot of literature saying it's not just volume of food, but what's been done to our food, the processing, certain ingredients becoming ubiquitous in the food supply, etc. I suspect it's similar with fish food as some of the same ingredients (like soy and corn derivatives) are common in fish feed and other ingredients in some products (feather meal as one example) are used because they're cheap.
Was a mod with Larry Johnson on an African cichlid forum for a few years and he said the same thing, especially aulonocara species being smaller in the wild. (Larry has been diving the lake for years on various research, conservation, and collecting trips.)
I think it depends on the type, though, and not a 100% rule. Some wild species can be just as big or some individuals bigger than most tank counterparts; even so, the wild versions may be slower growing and smaller at the same age.
Imo, wild fish of some types being smaller than tank fish isn't a huge issue in itself, a wild fish is likely expending more energy for less nutrient dense food, but that same fact argues for feeding less-- a wild fish expends more energy, often for less nutrient dense foods, so our fish often don't require as much some think.
But imo there's likely another factor, which is what's in some foods. Humans are statistically getting fatter and there's a lot of literature saying it's not just volume of food, but what's been done to our food, the processing, certain ingredients becoming ubiquitous in the food supply, etc. I suspect it's similar with fish food as some of the same ingredients (like soy and corn derivatives) are common in fish feed and other ingredients in some products (feather meal as one example) are used because they're cheap.
