Those sizes may have come of the website and other sources, but they are very conservative. yea, a few fish reach those sizes, the vast majority do not. the reference sources play it safe and typically list the max extreme rather than what is normal
Is my tank over stocked?
- Thread starter only6foot6
- Start date
Normal?
Define "normal" do you mean the stunted fish out of many beginner's community tanks? Or do you mean what they should reach in uncrowded and healthy conditions? I'll go with the latter definition myself. Probably the majority of hobbyists never see what their fish should be, or should have been had they not been kept in insufficient space. Nor do most hobbyists ever see how long their fish should live, part of the same issue.
We have not even touched on incompatability, although ChilDawg hinted at it.
Define "normal" do you mean the stunted fish out of many beginner's community tanks? Or do you mean what they should reach in uncrowded and healthy conditions? I'll go with the latter definition myself. Probably the majority of hobbyists never see what their fish should be, or should have been had they not been kept in insufficient space. Nor do most hobbyists ever see how long their fish should live, part of the same issue.
We have not even touched on incompatability, although ChilDawg hinted at it.
By normal I mean that what 80% to 90% of hobbyists experience. Perhaps you consider that "stunted", but that is the reality.
And just so we are on the same page, I follow the thinking that measurements do not include the tail - just the body.
Look at a few of the examples here -
Otto's @ 2 inches - Now, how many people here have Otto's that big? Even Dawes Encyclopedia of Freshwater fish notes the size "up to 2in reported but usually smaller".
Scissortail Rasboras - well, if we are getting conservative, Dawes reports "some up to 6in but usually considerably smaller". How often do you see a 3in Scissortail ? 2in is realistic
A Yo-Yo loach being 5 inches - sure, and I have some nice swampland in Florida that you may be interested in. I have kept loaches for many years and never saw one that large. In fact, Dawes notes "up to 4 1/2in reported but usually much smaller"
Those are just 3 examples. When calculating size in stocking a tank, we should use what is realistic, not the extreme. And that does not automatically mean using as you term, "stunted " fish. Instead it means throwing out the extreme hogh and lows and using what is typically found
And just so we are on the same page, I follow the thinking that measurements do not include the tail - just the body.
Look at a few of the examples here -
Otto's @ 2 inches - Now, how many people here have Otto's that big? Even Dawes Encyclopedia of Freshwater fish notes the size "up to 2in reported but usually smaller".
Scissortail Rasboras - well, if we are getting conservative, Dawes reports "some up to 6in but usually considerably smaller". How often do you see a 3in Scissortail ? 2in is realistic
A Yo-Yo loach being 5 inches - sure, and I have some nice swampland in Florida that you may be interested in. I have kept loaches for many years and never saw one that large. In fact, Dawes notes "up to 4 1/2in reported but usually much smaller"
Those are just 3 examples. When calculating size in stocking a tank, we should use what is realistic, not the extreme. And that does not automatically mean using as you term, "stunted " fish. Instead it means throwing out the extreme hogh and lows and using what is typically found
You are fully entitled to your own opinion, but personally, I disagree strongly. I don't think I've ever had a scissorstail Rasbora under 3" at maturity - even in the dark ages years ago when I was not nearly as careful as I am now.
The correct term is still (IMHO & IME) stunting.
I did not realize it was as bad as 80-90% of fishkeepers, but I suppose that is possible. I would have to interpret that as meaning that 80-90% of fishkeepers stunt their fish. Sad.
The correct term is still (IMHO & IME) stunting.
I did not realize it was as bad as 80-90% of fishkeepers, but I suppose that is possible. I would have to interpret that as meaning that 80-90% of fishkeepers stunt their fish. Sad.
It is my understanding that the lengths given are from head to tail, including the whole fish.
Regardless, if your fish are not full grown and you stock based on their current size, they really never have a chance of reaching their full adult size. Would you keep an entire spawn of goldfish in a 10 gallon tank for their entire lives, just because their size at a month old would have fit the one inch of fish per gallon rule? No! Because most would die before they reach adulthood, partly because they were not given enough space to live. Likewise it is IMO a little silly to overstock a tank with half-grown specimens and expect them to ever reach their adult size and/or be healthy and happy for life. Their growth will likely be stunted; even if their growth is not stunted, they are more likely to die before ever reaching their full adult size.
Regardless, if your fish are not full grown and you stock based on their current size, they really never have a chance of reaching their full adult size. Would you keep an entire spawn of goldfish in a 10 gallon tank for their entire lives, just because their size at a month old would have fit the one inch of fish per gallon rule? No! Because most would die before they reach adulthood, partly because they were not given enough space to live. Likewise it is IMO a little silly to overstock a tank with half-grown specimens and expect them to ever reach their adult size and/or be healthy and happy for life. Their growth will likely be stunted; even if their growth is not stunted, they are more likely to die before ever reaching their full adult size.
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RTR - well you too are fully entitled to your own opinion, and as you do with me, I personally strongly disagree with it.
I do not believe that because the majority of fish never reach the maximum size that it is because as stunting. There are reasons why their is a minimum and maximum size. The majority of fish fall somewhere in between.
Stocking based on the maximum size that even under pristine conditions very few fish will reach is extremely conservative and IMO silly.
Now, I am not saying stock based on existing size. instead, one should stock based on a reasonable average size. You picked one example out of the 3 I provided above. Lets me do the same. Look at the yo-yo loach. First off, Dawes doesn't even have them getting up to 5" - he has the max at 4 1/2". but ask most loach keepers and 3" is the norm for a healthy, full grown yo-yo. So IMO, one should stock based on the 3" norm, not the 4 1/2" extreme.
I do not believe that because the majority of fish never reach the maximum size that it is because as stunting. There are reasons why their is a minimum and maximum size. The majority of fish fall somewhere in between.
Stocking based on the maximum size that even under pristine conditions very few fish will reach is extremely conservative and IMO silly.
Now, I am not saying stock based on existing size. instead, one should stock based on a reasonable average size. You picked one example out of the 3 I provided above. Lets me do the same. Look at the yo-yo loach. First off, Dawes doesn't even have them getting up to 5" - he has the max at 4 1/2". but ask most loach keepers and 3" is the norm for a healthy, full grown yo-yo. So IMO, one should stock based on the 3" norm, not the 4 1/2" extreme.
Ottos at 2" is legit. We, as hobbyists, kill them so quickly that there is no possibility of learning what their full sizes will be. That having been said, I have had "Methuselah" for over five months now, and he is almost 1.5" from head to caudal peduncle. It is hard to tell the max. size of a fish when they are so hard to keep, but I would rather go by many literature maximums than risk losing fish due to overcrowding and stunting growth.
heady - well most of the people I have dealt with, including those I have discussed this with at my local aquarium society do not consider the tail in any measurements.
Next, you are completely missing or misstating my point. I am not saying to stock a tank based on a fish's size today. What I am saying is stock based on the reasonable projected adult size - not the maximum extreme's you have quoted.
IMO, it is very silly to base stocking on what 1 out of a large number of fish may grow to in pristine conditions. I am simply suggesting using norms and common sense.
Next, you are completely missing or misstating my point. I am not saying to stock a tank based on a fish's size today. What I am saying is stock based on the reasonable projected adult size - not the maximum extreme's you have quoted.
IMO, it is very silly to base stocking on what 1 out of a large number of fish may grow to in pristine conditions. I am simply suggesting using norms and common sense.
Okay, tag, superstein...we both got our posts in at approximately the same time, so "tag" is what people use to represent that, I believe.
Now I like your idea, but, being a statistician, I realize that there is an extremely high likelihood of fish living out "natural" lifespans and being within two standard deviations of the norm on either side--much higher than said fish only achieving the norm in growth. I would go a little more conservative than stocking for the norm, but I can somewhat see your point on the lit. maxes.
That does not, however, guarantee that lit. maxes are even close to right for captive conditions. Many of the lit. maxes stated for newer species are much too low, as are some for species which do not have a large following, just recently became available, or just recently became able to be feasibly kept by a vast amount of hobbyists.
I guess that we can all agree to disagree strongly and try to win each other over, but my $.02 are on the table and I hope to see conflicting opinions to repay mine soon.
Now I like your idea, but, being a statistician, I realize that there is an extremely high likelihood of fish living out "natural" lifespans and being within two standard deviations of the norm on either side--much higher than said fish only achieving the norm in growth. I would go a little more conservative than stocking for the norm, but I can somewhat see your point on the lit. maxes.
That does not, however, guarantee that lit. maxes are even close to right for captive conditions. Many of the lit. maxes stated for newer species are much too low, as are some for species which do not have a large following, just recently became available, or just recently became able to be feasibly kept by a vast amount of hobbyists.
I guess that we can all agree to disagree strongly and try to win each other over, but my $.02 are on the table and I hope to see conflicting opinions to repay mine soon.
Actually, there really isn't a huge amount of variability between fish in the wild. Age, gender and dominance within a system will impact size, but otherwise, most fish reach a pretty standard length. I know that when we do population studies, average variation within an age class in pretty minimal--less than an inch. That's impressive, statistically. I've seen the hatchery raceways with 50,000 fish, and there will be 6-10 fish that are more than 1 inch different in size, in either direction. The closer a fish is to F01, the more likely they are to be all the same size. In the wild, being much different in size that your age group is a serious liability. Bigger, and you have to compete with older, wiser fish, smaller, and you can't get as much food as quickly. Schooling fish of the same species will preferentially school with their own size, since the disparity in size makes them stand out, with means they are easily targetted by a predator.
Obviously, comparing fish from a huge reservoir with those from a tiny creek will reveal some huge differences. However, you can legitimately say that their environments impact growth rates. Hence, a fish that is 2-3 inches in the wild should be able to easily reach that 3 inch mark in a home aquarium, since they stresses and limiting factors found in wild populations (ie, food, pollution, competition) can be controlled in an aquarium. If anything, the maxes provided from wild fish may be under-estimates for the potential size the fish could achieve in ideal conditions.
Obviously, comparing fish from a huge reservoir with those from a tiny creek will reveal some huge differences. However, you can legitimately say that their environments impact growth rates. Hence, a fish that is 2-3 inches in the wild should be able to easily reach that 3 inch mark in a home aquarium, since they stresses and limiting factors found in wild populations (ie, food, pollution, competition) can be controlled in an aquarium. If anything, the maxes provided from wild fish may be under-estimates for the potential size the fish could achieve in ideal conditions.
