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How do you feel about the "1 inch per gallon" rule for tropical fish in general?

  • Not strong enough. You should stay under that.

    Votes: 0 0.0%
  • Good rule. Always follow it.

    Votes: 0 0.0%
  • I think it should be the "2 inch per gallon" rule.

    Votes: 0 0.0%
  • I think it should be the "3 inch per gallon" rule.

    Votes: 0 0.0%
  • No opinion.

    Votes: 0 0.0%
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well it all depends on the fish' girth if it is a very fat fish then no. a peerfect example are neon tetras very skinyn and small and can fit under that rule. so 30 tetras are okay. but anything biger, wider, fatter or any combo, you shoulld go under that rule maybe 4/5th of an inch per gallon. ur the artist and watever you make is your work and should be appreciated most by you (imo). make sure that its not overcrowded.
 

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Hi and welcome aboard.:wave:

1 inch per gallon is often not reliable. In a 10 gallons tank, you can actually keep more than just 5 neon tetras. Depending on wha fish you have, results will vary.:)

Thread moved.:)
 

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CE is "right on".

I did not participate in the poll as, IMHO, no option was applicable.

If anything the "general rule of thumb" should be modified to Volume of Fish/Volume of Water but

as Ce indicated even this "general rule of thumb" would very quickly break down for large fish.


One other item:

Fish (just as humans) require a given amount of protein.

Typically animal matter is higher in protein than plant matter.

Fish which are herbivores produce significantly more waste than carnivores or omnivores and hence would require a smaller ratio as well as increased biological filtration.


TR
 

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I agree with the others... the poll didn't really give a "good" option.
The biggest problems I see with "the rule" is that there tends to be lack of "common sense" for a lot of people...
I had a customer try to tell me that it was ok to put a 10 inch oscar in a 10 gallon tank... yeah.. right... poor fish (it died, of course).

The other problem I find too often is that people forget to count it as 1 inch of ADULT fish... instead they buy a baby fish and don't allow room for growth. A good example is a 30 gallon tank with 6 angelfish... because the angelfish are all only 1 inche each, it is thought to be ok to stock this way... but angelfish top out at 8 inches each, so the minute they start to grow, water quality and aggression levels start to become an issue.

There is no exact rule, as was already stated, but always work with a fish's adult size when figuring what size tank is needed.

Another note is that filtration and water changes say a lot, too, as well as feeding habits, species of fish, etc etc. A lot of good points were made in this thread, I would heed it all.
 

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bettababy said:
The other problem I find too often is that people forget to count it as 1 inch of ADULT fish... instead they buy a baby fish and don't allow room for growth. A good example is a 30 gallon tank with 6 angelfish... because the angelfish are all only 1 inche each, it is thought to be ok to stock this way... but angelfish top out at 8 inches each, so the minute they start to grow, water quality and aggression levels start to become an issue.
I would add that scalare angels need at least 18 inches height of the tank whereas altums will require 24 inches or more.:)

Good luck to everyone in this hobby.:thumbsup:
 

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Blue said:
[... I would add that scalare angels need at least 18 inches height of the tank whereas altums will require 24 inches or more. ...
Blue:

In West Texas if 3 is good, 5 is better but therefore I always get 7.

Hence the 30" tall tank which I purchased to raise angels (or discus: which Alex has "trashcanned" for a community tank) to full maturity.

Same with the Yoyo's, Cories and SAE's: if 3 are recommended, 5 are preferred I have 7!

TR
 

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I use 1"gallon as a starting point when planning a tank. I'll push it as high as 2" per gallon in a heavily planted, long established tank with a good surface area to volume ratio (3% or above) and overfiltration.

The shortest dimenstion of the tank shuld be at least twice the longest dimension of the largest fish (unless it's an eel or arowana or somesuch), and the longest dimension should be 3 times that at least, 4 times that even better.

Then:

Every fish starts with 1 point. Add 1 point for each of the following: Reputation for messiness or waste production, aggressiveness or fin nipper, fast swimmer or needs swimmng room. Knock off half a point for being long and skinny, very peaceful, or sedentary. Minimum is half a point, skys the limit. Multiply length by points and figure on that.

ie: Dwarf Puffer - 1", 1 point + 1 for Messy + 1 for aggressive = 3 points, figure as if it were 3".

Make adjustments to the plan as you add stock. If you look at the tank and think, that's overstocked, then it probably is.

As Dawn pointed out, always figure on maximum size, not current size. The one exception: if you're trying to figure out if you can hold a fish in an established tank while you cycle another tank for it, go ahead figure on double the current size or the full size, whichever is less. (And that is, I think, pretty conservative.)
 

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Well I have 17 neon tetras and 1 glowlight and 2 BN pleco in a 10 gallon, HEAVILY, planted and have not lost a fish in 6 months nor have had any stress related issues. The tank is very welll established and I tested it often to establish that the tank could handle the bioload before going that heavy.

According to every rule, massively overpopulated ut the neons have the best colors I have ever seen in them and the BN almost have irridescent color to them.
 

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All I can say to that one is that if enough water changes and filtration is offered, it's not impossible for shorter term, but 2 bristlenose, if healthy, will outgrow a 10 gallon tank, not just because of waste, but size. If starting with small enough bristlenose, it may not look like a lot now.... 6 months isn't really a "long time" in the life of a fish that lives 20+ years. If healthy, they will grow, in spite of the size of their tank, and I've seen some horribly disfigured fish raised this way. It was very sad to see.

I once had a customer bring in a jack dempsey... it was about 10 inches long and the most brilliant colors. The guy did a 100% water change daily, and fed 3 times/day with some good and nutritious foods. The horrible part about the situation was that the fish, while beautiful, had a spine that was kinked the entire length of the fish. When we put the fish into a 40 breeder quarantine tank, with perfect water chemistry and extra filtration, the fish was not able to hold itself upright or to swim... it just laid on its side in the same spot we had put it when releasing it into the tank. A little over a week later, the fish died. That fish was 2 yrs old... should have lived to be 30 - 40 yrs, at least. The man explained to us that he'd bought it at about 2 inches in length 2 yrs prior, took it home to his 10 gallon tank, and was content with that one fish for 2 yrs... but "got bored with it cuz it didn't do anything", and decided to get rid of it.

I guess what I'm trying to say is that just because we CAN do something doesn't mean we SHOULD do it... and that not everything we do is good for long term situations. My last neon was with me for 10 yrs... so I know these fish have the long lifespan if they're provided for properly.
 
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