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How Many Fish Can I Keep?

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How Many Fish Can I Keep in my fish tank?
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ShrimpRetirement
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Depends on your plant mass, tank size, filter type/size, and amount of flow you got going on. From my experience, you can keep more fish as you up the sizes/amount in these listed elements. I keep around 50 fish & 10 shrimp in my 39g. The bigger the plant mass, the more of a bio filter you have. The bigger the tank size, the more room your fish have to play. The bigger the filter, the more flow you'll have for sending all essential nutrients to plants so they can keep growing to sustain our bio filter system. Just don't go overboard.
 

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How Many Fish Can I Keep in my fish tank?
Your question is vague and you have included zero info about your tank, the kind of fish you want, etc. So right now, your question is completely useless.

A general rule is 1 inch of fish for each gallon of water. 4 inch fish = 4 gallons of water.
So I can keep a 12 inch oscar in a 12 gallon tank? Awesome!
 

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Only if chopped up into 1" pieces!
ok, I just did that. My oscar is no longer moving, and my water looks like it needs to be changed (though I changed it when I moved the oscar.) :confused::confused::confused::confused::confused:
 

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Pingu789: As subtly suggested by the others, if you give some additional info you might get more than the infamous but delicious Oscar Massacre Stew in response...

size of tank
equipment available (for filter, circulation)
plants
how established is the tank? (Definately read on other threads on this website about 'cycling' a new tank)
Do you have specific fish you were considering?
 

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the general thumb rule of 1" of fish / gallon is ok for a beginner but too generic. Like others said, provide some details of the type of setup you plan. That will help to make suggestions.
 

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I found this! helped me understand.

The "one inch per gallon" rule

This is something that comes up fairly often and is rather misunderstood therefore I will attempt to clarify the original meaning of the general guideline of "one inch of fish per gallon of water".

This is a suggested guideline for a well maintained and filtered tank.
It does not apply to all fish as some have differing requirements.

Here is the part that is being misunderstood.

The "rule" does NOT refer to the length of the fish!

The "rule" applies to the cubic inches of fish in the tank.

This means that a 5" gourami should be measured in this manner,
length overall (5"),
thickness, (1/2"),
height, (2 1/2"),
so for this fish you multiply the following, 5x 1/2x 2 1/2, this gives you a total of 6 1/4 gallons of water.

For small fish like glo-light tetras you will end up with something like this,
1 1/2"x 1/4"x1/2", this comes to 3/16 of a gallon (about 1/5), and that gives you 5 fish of this size per gallon (quite reasonable)

For larger fish you end up with something like this, my example here will be a silver arowana at 24" long, 24"x 4"x 1", which gives you 100 gallons of water.

As you can see this works fairly well.

You do also have to apply some common sense and allow for such things as potential growth, the fish types' tolerance for crowding, and of course the width and length of the tank (a 24" gar will not work in an 18" wide tank even if the tank holds 100 gallons).

So please people, accept that this is just a generalized guideline to figure potential stocking levels, not a hard and fast rule.
Also remember that just because you don't like it doesn't mean you should slam somebody for using it.
And lastly, please don't flame someone by saying a 10" oscar doesn't fit in a 10" tank.
Of course it doesn't,
but the rule never said it would.
 

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For small fish like glo-light tetras you will end up with something like this, 1 1/2"x 1/4"x1/2", this comes to 3/16 of a gallon (about 1/5), and that gives you 5 fish of this size per gallon (quite reasonable)
I think this is a little too liberal. I have a 90g tank, but I certainly don't keep 450 tetras in it.
 

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I found this! helped me understand.

The "one inch per gallon" rule

This is something that comes up fairly often and is rather misunderstood therefore I will attempt to clarify the original meaning of the general guideline of "one inch of fish per gallon of water".

This is a suggested guideline for a well maintained and filtered tank.
It does not apply to all fish as some have differing requirements.

Here is the part that is being misunderstood.

The "rule" does NOT refer to the length of the fish!

The "rule" applies to the cubic inches of fish in the tank.

This means that a 5" gourami should be measured in this manner,
length overall (5"),
thickness, (1/2"),
height, (2 1/2"),
so for this fish you multiply the following, 5x 1/2x 2 1/2, this gives you a total of 6 1/4 gallons of water.

For small fish like glo-light tetras you will end up with something like this,
1 1/2"x 1/4"x1/2", this comes to 3/16 of a gallon (about 1/5), and that gives you 5 fish of this size per gallon (quite reasonable)

For larger fish you end up with something like this, my example here will be a silver arowana at 24" long, 24"x 4"x 1", which gives you 100 gallons of water.

As you can see this works fairly well.

You do also have to apply some common sense and allow for such things as potential growth, the fish types' tolerance for crowding, and of course the width and length of the tank (a 24" gar will not work in an 18" wide tank even if the tank holds 100 gallons).

So please people, accept that this is just a generalized guideline to figure potential stocking levels, not a hard and fast rule.
Also remember that just because you don't like it doesn't mean you should slam somebody for using it.
And lastly, please don't flame someone by saying a 10" oscar doesn't fit in a 10" tank.
Of course it doesn't,
but the rule never said it would.
I do not think anyone was trying to "flame" anyone here, it was just that the question was so simple and it was obvious little attempt was made to use the search tool or read through the archives for an often asked and many-times answered question. Very nice of you to take the time to repeat it all here for them. But it just encourages people to just keep taking the lazy route! :bounce:
 
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