Full Grown Oscar in a 20 Gallon. 1 inch per gallon?

[Orion]

Ok so yeah, the title was pretty much just to get your attention. But it draws upon a very good idea.

A lot of folks new to the hobby like to go by the guideline of 'one inch of adult fish per gallon of water'. And this is fine for a general guideline to get started in the hobby. However, this theory quickly breaks down when you get away from the common community tropical fish.

Lets look at the above example: A full grown Oscar can easily be anywhere from 12-15 inches long as an adult. By thinking of the inch per gallon idea, then it should be fine in a 20 gallon right? At most, 15 inches in 20 gallons so we've even got 5 inches of space left over. Eh, not quite. This is where the idea breaks down. An oscar is no where near a common community fish. Before we even take into account it's length, check out an adult oscar's shear width! I've seen many an adult thats been 2 inches thick easy. Also, an oscar has a LOT more energy and strength than your community fish, and this needs to be taken into account as well. Next lets look at what comes out of the oscar. They are notorious for being messy eaters, as well as big time poo'ers. It just doesn't make since to keep a fish like this in a 20 gallon tank, even though it may fit into the inch per gallon bracket.

There is a time and place for everything. And I'm not trying to say that the inch per gallon idea should be bannished and forgotten forever, not at all. I think it certainly has it's place to help people get started in the hobby, and works so long as it's applied to common community fish. I do however feel that it should be realized that it is just an idea, and by no means a rule set in stone. Each persons tank is different, and what works for one person may not work for the next. That's why this hobby is so often an art form of finding the balance of what works for each of us.

Feel free to discuss.

 

[roark fishies]

I've also read that fish who are "tall" need more space than the 1" per gal rule. For instance, a discus is going to need more than 1" per gal because their bodies are not just long but tall as well.

As for Oscar's in a 20G, look at it this way: Would you want to live in a house barely big enough for you to turn around in? I feel bad for Oscar's that not in a HUGE tank.

 

[cchase85]

I agree. I also think it's ridiculous to consider a school of five neon tetras to be fully stocked for a 10 gallon tank, yet there are many who would argue that.

I think it's much easier to stock more fish into a tank if the fish are individually smaller than having singular, large specimens. There's nothing overcrowded about 30 neon tetras (to use the same example) in a 30 gallon tank, while two 15" oscars would be ridiculous.

And it's not just an issue of waste produced or space to swim.

 

[punkrockfish]

do we have a sticky dedicated to how untrue this rule is?

 

[FishGeek]

Very Well Said Orion! *thumbsups

 

[Big Vine]

I agree!



<------ and Mr. Triton over here (picture Michael Clarke Duncan's voice) says 'thanks, boss'!



BV

 

[TabMorte]

I think that the 1" rule's mostly helpful for small tanks and new fishkeepers (and inexperienced pet store people) though, it keeps inexperienced people who have just bought thier first 10G tank from putting like 50 neons in it. You know?

 

[Orion]

Mr. Triton is welcome

I was just using an oscar as an example, but many more fish can also be seen as why this idea breaks down when you get away from typical community fish. And I'm not trying to come down on anyone either, just reiterating the point that this is just an idea, not a rule. Rules are too be followed, idea's are to be kept in mind.

Like many have already said in this thread, the idea is very helpful to those new in the hobby and I couldn't agree more. But it also just needs to be taken with a little grain of salt as well and understood that not every situation calls for the 'inch per gallon' idea.

 

[d3sc3n7]

I couldn't agree more with Orion. However, I agree with Cchase also. I think that fish the size of neons, or glofish, or guppys, anything very small like that, could be more considered as 1 fish per gallon. They are so small, and put out so little waste...I really believe you can keep more of them in a smaller tank. Using that idea...an over stocked 20g neon tank, would house > 20 neon. See what I'm saying?

 

[MissFishy]

I see everyone's point on this and definitely agree. I do, however, find it extremely perplexing and annoying when I give out this "rule" to newbies on the site, then a dozen people post after me telling the newbie how untrue this is and how they can stretch the limits, it's not really a good rule, etc. It has it's time and place, but once you know enough to know this isn't really a "rule" then obviously you have a grip on the hobby and what is a fully stocked tank.

I guess in the future I would surely appreciate it if all you folks that dislike this rule don't go bashing it to newbies who have no idea what they're doing in the first place and henceforth find the "rule" a helpful guideline when stocking their first tanks. Obviously, you all have an inkling as to what is suitable stocking levels in a tank and do not need to bother with this guideline further. I try to take the time out to give some sound advice to the newbies that come to this site for advice and find it extremely difficult when people post behind me telling these folks that what I just said isn't really true. They find it confusing as well.

The general advice I dole out to those seeking some stocking guidelines are these:

1 inch of adult fish size per gallon of water in your tank up to a 4" inch fish. i.e. this rule does NOT apply to oscars as they obviously grow to larger than 4".

20 gallons of water for one goldfish, then an additional 10 gallons for each additional goldfish after that. This of course only applies to the smaller ones, not the pond busters, then again, I don't see many newbies buying $50 pond size goldfish and shoving them into 20 gallons.

Cichlids (south american, etc.) I consider a different realm entirely. Since I have little experience with these, I don't pretend to know what I'm talking about besides the general behavior patterns, and thus try not to give any stocking advice here.

 

[d3sc3n7]

MissFishy...I agree with your points...and think they should really be put in place. Everyone is entitled to their opinion, but it should not come off like this.

Ex. Post: Well, I don't think you should put that many fish in that small of a tank.

Next Ex. Post: Hey "nick", dont listen to "previous poster", you can stretch it, and get a few more fish in there. It's fine.

yet, I see this all the time. It should be more like this

Ex. Post: Well, I dont think you should put that many fish in that small of a tank.

Next Ex. Post: Well "nick" I'm not saying "previous poster" is wrong, but in my opinon..you will be ok with that many fish.

These newbies (me included) are here searching for advice...and if people are posting 4 different views on the question, you get really confused, and have no idea what to do. Then your even more lost than when you started.

 

[marvin]

Ok so yeah, the title was pretty much just to get your attention. But it draws upon a very good idea.

A lot of folks new to the hobby like to go by the guideline of 'one inch of adult fish per gallon of water'. And this is fine for a general guideline to get started in the hobby. However, this theory quickly breaks down when you get away from the common community tropical fish.

Lets look at the above example: A full grown Oscar can easily be anywhere from 12-15 inches long as an adult. By thinking of the inch per gallon idea, then it should be fine in a 20 gallon right? At most, 15 inches in 20 gallons so we've even got 5 inches of space left over. Eh, not quite. This is where the idea breaks down. An oscar is no where near a common community fish. Before we even take into account it's length, check out an adult oscar's shear width! I've seen many an adult thats been 2 inches thick easy. Also, an oscar has a LOT more energy and strength than your community fish, and this needs to be taken into account as well. Next lets look at what comes out of the oscar. They are notorious for being messy eaters, as well as big time poo'ers. It just doesn't make since to keep a fish like this in a 20 gallon tank, even though it may fit into the inch per gallon bracket.

There is a time and place for everything. And I'm not trying to say that the inch per gallon idea should be bannished and forgotten forever, not at all. I think it certainly has it's place to help people get started in the hobby, and works so long as it's applied to common community fish. I do however feel that it should be realized that it is just an idea, and by no means a rule set in stone. Each persons tank is different, and what works for one person may not work for the next. That's why this hobby is so often an art form of finding the balance of what works for each of us.

Feel free to discuss.

wow you are realy hung up on this one inch thing orin guess i am a newbie the ''rule'' is to pre plan how big that little two inch fish will get and not to over stock. if you have as many thaks as this newbie has one inch is no prob.I can move fish around again the one inch is pre plan for fish growth and another un written "rule" is moct fish in a community seting will grow to the sixe of the tank...

 

[Orion]

I'm not really sure what you are trying to say marvin, but I am certinaly not hung up on the idea, either pro or con. My point in this is to help new people realize that it is only an idea to help get people started in the hobby. As has already been said, most people don't even think about this once they've been into the hobby for a while because they have a good idea about whats going to work and what won't. There is a whole lot more that contributes to a balanced ecosystem than simply the number of fish, and sticking with a simple idea like the inch per gallon helps eliminate a lot of problems that otherwise might creep up in a new tank allowing them to enjoy it more without worrying so much.

But there is a time when the idea tries to become a rule that everything breaks down, and like most rules this is where it goes bad. But for the most part, it is a good thing. Like I said, it just needs to be taken with a grain of salt and people should at least realize that it doesn't work all the time, every time.

And trying to compare the number of tanks you have is simply ridiculous. Whats your point with this?

Fish do not grow to the size of the tank they are in. They get stunted, which is very unhealthy for them because while there bodies stop growing, the internal organs do not and eventually cause death due to the organs being overcrowded.