Our view on stocking levels and the stunting of fish.

[Cichlid Man]

One of the most common questions asked concern how to stock a fish tank. This is particularly true in the more general forums that are frequented by newcomers to the hobby. These questions often take the form of, “How big of a tank do I need to keep such-and-such fish?”

We at Fishforums.com stand by our recommendation that doing what is best for the aquarium inhabitant is of more importance than any other concerns or desires you may have.

The Old One-Inch-Per-Gallon ‘Rule’ is basically a myth as it only applies to the small tetras or similar fish.

The needs of the fish or animals should be taken into consideration. These needs may include;
* Proper room for the Activity Level and Swimming space - Swimming levels/niches, the animal’s usual style or level of activity such as ‘laps’ around the aquarium, schooling, and skittish behavior common in schooling fish.
* Territorial requirements – the floor space or empty room between individuals.
* Vertical space - most taller-bodied fish require room above and below their fins.
* Compatibility issues- many aquarium inhabitants will not be able to live together properly to the end of their natural life spans.

Aquarium manufacturers now offer customers a wide range of different shapes and sizes of tanks. It is fairly standard for companies to offer multiple tank configurations for a given standard size. For example, 20-gallon tanks often come in a “high” configuration (24” long x 12” wide x 16” tall) or “long” configuration (30” long x 12” wide x 12” tall).

Any animal whose destination is to be kept in captivity as a pet has the right to live in an environment that will not severely stunt its growth and will not severely shorten its natural lifespan. Discussing what are the appropriate conditions to meet these criteria is fine, but arguing that it's OK to stunt a fish and decrease its life expectancy is not. Those that disagree with this community's philosophy on these issues should feel free to search for another board that is more compatible with their point of view.

CREATED BY MODERATERS FROM NUMEROUS FORUM SITES.

[malawi4me2]

Well said!

[Damon]

Wow. I couldn't have said it any better myself! lol

[Osiris]

very well said, it is a consipiracy! Down with the "Inch Rule" !

[ImagineAquatics]

I will take this into consideration when I re-rate the capacity of our aquarium. I dropped a bombshell when I stated the amount of fish it could 'keep alive' on another board. It was excessive and absolutely maximal. My company makes a small tank (usually holds around 6 gallons of water after gravel and such), and our ratings are based on filter's ability to eliminate ammonia and nitrite, and to keep fish alive, not to keep them happy, or to give them their max life span. Our tests ran for 6 months to 1 year for the most part.
Our prototypes have been running longer, but conditions are optimal. I realize the error in my way here, and will reevaluate our 'inches' rating. But that begs the question, how exactly does one rate the any aquarium system?

Is there a good way to express the effectiveness of an aquarium system without using an 'inches per gallon' or some similar system? How should a manufacturer present the realistic stocking requirements per aquarium if the area is so complicated, and the species are so diverse? Most consumers don't understand everything that goes into making an aquarium work correctly. They need 'something' that gives them an idea how well their equipment will work. Any ideas?

It's like with computers. How does a computer company represent the speed of a processor. Mhz used to be the standard, though it never truly represented the actual processing power of the computer. It was more of a marketing tool. intel has pretty much dropped the Ghz rating system in favor of a model number system (which is terribly confusing to consumers).

I've done a lot of thinking about this that last day or so, and I believe what you and many others on these forums are expressing is true. Ethically one needs to explain exactly which fish can be kept not only alive, but happy and healthy. Truthfully, I had never even thought about it when I rated the capacity of our aquariums. I was looking at it from a manufacturers perspective, and not a hobbyist's perspective. I wish that someone would think of an alternative. I was thinking about providing 'cook book' formulas for proper live stocking. Are there any good ones? Our tank has 20"x5"x18" of space and a filter that you can assume will do the job very very well. What will thrive? I would like to find some combinations that are aesthetic, fairly easy to find and purchase, that will live in the aquarium for their full lifespan, get along with each other, etc... Any suggestions are appreciated!

For the record, when I service and stock tanks for customers, I never put anywhere near the maximum rating in them. I may have made a few mistakes using fish that eventually outgrow the tanks, but those will be corrected. Most customers find that a tank of this size and shape appears very full with far fewer fish.

Thanks for the reeducation! You've done some good for all of the fish that will be guests in our aquariums.

[Fishfirst]

well with your bread and butter fish like guppies platys mollys tetras corys and rasboras a good rule of thumb is 1" per gallon. But in your company's case I'd consider your filtration unit more than optimal. You could probably get by with 1.5" per gallon of these fish to up to 2" per gallon. BUT remind your customers that the more fish you've got the more things can go wrong and the more you need to clean. An understocked tank would be the best for minimal maintenance, moderate maintenance go with 1" per gallon and high maintenance 2" per gallon. It also depends on the activity level of the individual fish species. Some tetras would like a little more room as well as danios.

[Thunderkiss]

My only addendum i'd make is to bannish the myth that fish stunt due to confined spaces.
Fish don't stunt, they deform, yet continue to grow. 'Sides that, VERY well said

[Cichlid Man]

Quote from Dr axlerod in his book of fish health:

Originally Posted by Cichlid Man

If regular water changes are not made regulary then a fishes growth will be serverly stunted if the tank dimentions are too small for the fishes potential size.

[garfieldnfish]

The 1 inch per gallon was never more then a guideline. The poop factor of a fish also needs to be considered and like stated the activity level, swimming room needed and compatability between fish, planted or not, decorartions etc all need to be taken into account. But that is why people ask these questions. Fish have individual personalities as well and what works in one set up may not work in another identical one. Everyone should research the fish they would like to add to their aquarium, find out who is the best for cycling and how to add them one by one so the less aggressive one can establish a territory first. That of course only happens in the perfect world, hence we have Walgreens, lol.
Most people buy an aquarium, listen to the LFS clerk and throw a bunch of fish into the tank. After loosing many, the remaining fish may get lucky if their owner tries to find out what went wrong by reading and asking questions in a forum like this one and may thus save the lucky ones.
I know I started out this way 2 years ago. Now 11 tanks later, I am breeding fish and like to think all my critters are happy. But it took a lot of research and we should not tell people to go to a different site just because they use the inch per gallon guideline. If they do that, it's at least a step in the right direction, the rest of this complex hobby needs to be explained but everyone needs to start somewhere.

[honmol]

I have a 6 gallon tank for one of my bettas and she's very active. She uses the entire swimming space and when I got a couple otos to be with her the tank seemed overtocked to me and I moved them to a different tank. As long as you have active fish you don't need alot of them for a tank. As for the inch per gallon rule, I go by it for small, thin bodied tropical fish usually but even then there are exceptions.

[leveldrummer]

no one really thinks about the stunting of a fish, if you put a new born baby into a plexiglass box when it is born, and feed it and change but always have it in the box, the baby will be stunted and terribly deformed. usually malnurishment comes into play as well, most people think thats the most terrible thing to think about, a baby in a box like that, but those same people have an oscar at home in a 20 gal tank.

[ron v]

Level, I agree with you. And to make matters worse, these small tanks tend to be chosen by newbys who are not familiar with tank maintainance so not only are the fish confined, but are in bad water also.
ImagineAquatics, I appreciate that you are on here asking questions. You care and that is to be admired. If I were you, I would market your 6 gal. tank to advanced hobbyists like betta keepers. There is a place in our hobby for tanks of that size but in my opinion a beginner should start with a larger tank.

[micstarz]

That is very well said CM! imagineAquatics, I suggest a betta with a snail and a ghost shrimp.

[Puffer Pita]

Hate to dredge up an old topic but what would you say to someone who told someone else that was having a problem with a crab eating his other fish that he should cut off one of the crab's thumbs to prevent it from snatching the other fish (don't worry, it'll grow back eventually) and that he could then stunt the crab so it wouldn't outgrow the tank. Would you say his answer was out of line or would it merely be valid and informational?

[Cichlid Man]

I would say this would be completly the wrong thing to do. For a start intentionaly stunting an animal knowingly would be pointless and stressful for the animal. Any animal should be given enough resources to thrive and grow to it's full potential. A stunted animal is not healthy, or wasn't for a long period in its life, and why buy a crab that eats fish for an aquarium which contains small fish anyway?

[Puffer Pita]

Ok, thank you, that's all I needed to know.

[bernte]

yes thanks!


greetz bernte

[foehammer306]

That is very well said, whoever made the one-inch rule is a liar.

[Spiderpig]

hm, well, i read a lot of books on aquariums and such and most all of them said that for tropical tanks, find the total surface area of the water then divided by 12 and the number you get is how much inches of fish you should have in that tank(exclude the tail)

Anyone else ever here of this stocking level rule?

[Mitten]

Spider Pig, with that formula, for a 10 gallon, you get 15 inches of fish.

That seems like a lot of fish