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I was just thinking, when figuring out the carrying capacity of a pasture a lot of people in Australia use the Dry Sheep Equivalent- a measure of how much feed an animal needs in relation to the smallest unit - a 45kg wether. For example a steer would be 8-10 DSE, a ewe with lamb would be 2.4......and so it goes on for anything you might want to put in that paddock.

I know there are other tank stocking guides out there, from 1cm fish per litre to complex surface area calsulations, but they've often been said to not work, or to only work for certains hapes of fish.

So, would anyone be intrested in contributing experience and ideas to the development of a new stocking system: The Neon Tetra Equivalent.

It would work like this- assume a standard rectangular tank, and how much surface area it has. Then figure out that FishX requires the same ammount of space as X Neon Tetras.
For example- 1 Betta would be 5 NTs.

Would this system make things too complicated, or would it actually be useful to anyone?

<Vet in Training>
Blog under development: http://www.nearlydrferox.blogging4life.com/

It could be useful, but, I think in the long run it all depends on the aquarist. If they arent going to do regular water changes and other tank maintnance, its not going to work.

Would it just be based on metabolism or biomass? For example, a goldfish produces considerably more waste than a cichlid of equivalent size...

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It would be equivalent mass- whichever requires the biggest space out of metabolism or size. You then convert thatt o how many neons you could keep instead, so you can compare the requirements of different species.

<Vet in Training>
Blog under development: http://www.nearlydrferox.blogging4life.com/

It would be good to have, though I doubt my maths would be sufficient for assisting. If I can help in any other way though, just let me know

Maintenance concerns and other impacts would be the same regardless of the environment, be it tank or paddock.

Primary problem I see would be that, unless many things were factored in (water chemistry, exercise requirements, food types, etc), even if you assumed that maintenance was a constant it would most likely end up having the same or similar limitations to 1"/USG type rules with the appropriate exceptions.


Can you link to a good DSE explanation so we can have a squiz at what it covers?

For animals, the entire universe has been neatly divided into things to (a) mate with, (b) eat, (c) run away from, and (d) rocks. - Terry Pratchett

http://www.dse.vic.gov.au/DPI/nreninf.nsf/childdocs/-89E7A8DAFEA417624A2568B30004C26A-D84473774162CFC3CA256BC7008115C7-2DBF9830AA3DF6534A256DEA0027B575-CFF9963950B3CC13CA256BCF000BBFF4?open

The DSE system basically works on feed, as agriculture doesn't worry too much about how close animals are to each other.

For fish, I'd replace the feed requirement with the space requirement, which would take into acount activity, size and waste production. It would be in comparason to a neon tetra kept in the same conditions.

So, for example, if a Bronze Cory is 3 NTE's, then a school of 6 corys would have the same space requirements as a school of 18 neon tetras. It doesn't take into account how much food they need, but how you could stock a tank.

<Vet in Training>
Blog under development: http://www.nearlydrferox.blogging4life.com/

So it would be almost the inverse of the agricultural forumla, working on a set of biological needs other than food, yes?

If I'm following you here, this would be awesome! How can I help?

I vote! Do you?

Wow what an awesome idea.

Although I would be more concerned at the waste output of each type of fish. Because it's the waste that is the killer (pardon the pun). Goldfish versus Discus for example. Same weight fish say but one being a bigger polluter than the other...

It would be handy to have it so that if you're someone that moves fish around as they grow bigger you can work out FishX's likely requirements based on his size. But my mathematically challenged brain boggles at the thought of working out the first part, so maybe this could be a stage 2 project...?

I dont wanna be a downer on enthusiasm, but its weight vs mass vs metabolism vs digestive efficiency vs nitrate tolerance vs water change sensitivity vs temperature vs diet content vs gaseous saturation vs ph vs hardness vs bacterial growth rates, vs ionic exchange vs energy consumption equation.

There are too many variables that change according to species for there ever to be a calculated rule that works on anything more than a narrow range of fish type. On top of that you have to throw in filter efficiency before you can get results, and that mean calculating average densities of bacterial population in response to available mocropore availability, flow, and available food.

I dont think there will ever be a shortcut rule to fish stocking, and thus far in fishkeeping history such rules have done more harm than good. Its an interesting subject but you could probably have driven einstein insane working it out. Whatever formula you work on it will have to work on a logarythmic scale, and would still be governed by intervening moderations according to tank setup as tank efficiency changes with sise due to incluse microhabitats and environmental stability. Its actually quicker just to take on fishkeeping experience and work it out with small variables youre not even truly aware of. There isnt a standard stable average condition that takes into account individual environmental conditions and there isnt a stable formula to initiate calculations from.

Put is this way, the problem is so technical, NASA have been working on closed ecosystems and they never cracked it.If you did crack it, youd be worth millions,and even then youd still have to have backup equations in case of loss of equilibruim, and that means in the final analysis, no matter what your equation is , you still have to make intuitive adjustments.The end result would still be an average , and liable to change vs time. In short be just like a fishkeeper is now, learning estimation as a fine art as they go, more than as a mathematic formula. The principle is kinda called "suck it and see" LOL

Its a bit like that with carbon theory too. Its taken tens of thousands of scientists to tell us that the world might be under threat from co2, when all that was necessary was to watch the seas forests etc and know that you dont know enough to mess with it or be cutting it down, or polluting stuff. The shortcut is the human brain, not formulae.

Not that id ever suggest you not try to work it out, imagine what a living legend youd be if you did, but it might be.........extremely effing bleedin difficult! LOL

Then there the practical application of it. In terms of averages we now that mass is a better average of the sort of stuff were working out here, but that means millions of people would have to start weighing fish for there to be an improvement over the fish per inch rule. Trust me, we wont even get them to do that.


Sum total of my estimation of the facts is that we already know that safetly is in supersizing things, giving animals a bigger environmental space than they really need on the limit to inbuild a margin of safety,and if people want to cut fish accomodation sizes down to the bare minumum, they will always, always get problems.

Ergo life isnt about producing minimum tanksizes, and when you produce an equation, people will always, always try to get as close to the bare minimum as possible, and when you take the intelligence and behaviour of the fish into account, and add aspects of humane care, the chemical output of the fish becomes almost irrelevant. Tanksizes never have and dont rely on minimum equations based on chemistry, it should be based on standards of humane care, and thats why we dont give formula to fish based on the properties of chemical reagents.

Behavioral aspects of all species make them what they are, and define how population density works on planet earth combined with the uneven spread of resources. It is that behaviour that keeps animals from wiping themselves out. We dont have a system that is better than that set of natural instincts, so perhaps the timme of the aquarist is better spent promoting humane care , since it generally doubles average minimum standards of chemistry related issues anyway. The real solution is right in front of your eyes ladies and gentlemen. Follow natures cues, and dont get bogged down in a finite and entirely human point of view.

We know bettas dont belong in 1 gallon tanks because not only is the water chemistry a positive liability, being that its right on the edge, we know that never in a million years will a betta be fit in that space of water, and that it will quite probably suffer mental injury and steroeotypical behaviour from such housing, and we know that in a 5-10 gallon will be enough room for it to be fit ,and will have almost no chemistry issues, in facts its at least ten times less likely to get chemical issues. The behavioural observation saves the fish, and you find that to be true in almost every species of animal on planet earth. The mechanism for correct environmental sizes is already intrinsic to every creature on earth, except us apparently. Farming is about intensive food production, I dont think its a healthy parralel for fishkeeping. Maybe for commercial fishbreeding for food, but never for a pet expected to live to full longevity. Farming and pet culture should stay seperate. Because we love our pets, not kill them for food, we should be expecting to exceed minimum sizes of accomodation as standard. Thats what good fiskeepers do, and it doesnt really require much in the way of calculus, we just take a reasonable standard for water chemistry , and double, triple it, quadruple it, or more, therefore bringing safety and happiness to our pets,. So it could be said that a formula id accept has to be double or triple minimum values, and tempered with behavioural observation. But margin is so much higher, I dont need a formula to do that.The only formula I do actually need is to know that my filter is up to the job, and since I overfilter anyway, thats also not a remote problem I need an eqaution for.


Maths.Bummer aint it? Makes you forget what you were trying to do in the first place