1" fish = 1 gal, but...

[demurefemme]

I have always wondered exactly what is included in that number, and have always heard differently...so I'm just gonna ask my (probably stupid) questions, and see what y'all have heard.

Do you include bottom feeders (catfish) and/or algae eaters (CAEs)? I've heard it both ways...
and
Is it tail *included* or tail *excluded*? (once again, I've heard 'em both).

Thanks!

 

[gchen]

Well, a fish's mass goes up with the cube of its length, so the rule of 1 inch of fish for each gallon probably only holds for small fish. Ten one-inch fish can occupy ten gallons of water, but one 10-inch fish would need a 55 gallon tank!

 

[mgkaelen]

the "inch" scale does NOT include tail, but does include everything in your tank... not only does it account for spaciousness, but also keeps a basic check on your bio load..

 

[tkos]

Yes, of course it includes bottom feeders. I guess the idea that it wouldn't is simp;y looking at swimming space. But bioload and not swimming space is the main thing you should look at. But as was mentioned it really only works for fish like tetras.

Many bottom feeders actually produce much more waste than fish like tetras. Oh and a CAE is a really poor algae eater. Look at SAE for that job.

 

[Bearfan]

There are big differences in the algae eaters. Here are some profiles I did a while back:

Siamese Algae Eater (SAE):
http://www.aquariumadvice.com/viewtopic.php?t=5524

Chinese Algae Eater (CAE):
http://www.aquariumadvice.com/viewtopic.php?t=5526

Flying Fox:
http://www.aquariumadvice.com/viewtopic.php?t=5525

False Siamese Algae Eater:
http://www.aquariumadvice.com/viewtopic.php?t=5527

 

[TankGirl]

The 1" per gallon rule is very difficult to adhere to, unless you are stocking only tiny tetras. You have to consider the fish's impact on the bioload, and do not overlook things like snails and shrimp, which produce a lot of waste. Different types of fish have different gut configurations and therefore process waste differently, so all 1" of fish are not created equal.

 

[ferret]

If the fish is over 3 or 4 inches, the inch rule does not apply. Maybe even 2 to 3 inches.

 

[Centurion]

i know bearfan gave you 4 links, but i found them all nice and together: http://www.bettastarz.com/sae.htm check that out. i can now go to the lfs and examine the fish and see the differences.

 

[mgkaelen]

is there any thread talking about what kinds of fish produce what kinds of bioload? it would be very informative... !!

 

[TankGirl]

is there any thread talking about what kinds of fish produce what kinds of bioload?

There may be, but I can't recall a specific one. Basically your plecostamus type fish are heavy waste producers, as are large cichlids. Snails like the mystery or apple snail produce a lot of waste as well. I am sure there are more, so hopefully someone will post other poop factories. I think Allivymar has mentioned her otocinclus are heavy waste producers (they would fall into the suckermouth cat category, like the pleco), but I have not noticed this with mine, though I may have been blaming it on my snails!

 

[BrianNY]

Has anyone considered that the 1 inch rule goes back to the stoneage? Surely the filter technology has improved since then.

 

[stoneydee]

And of course, there are goldfish. . . but you seem to be talking about tropicals.

 

[TankGirl]

Oh yeah, do not leave out the goldfish! How could I have forgotten...

What it boils down to is researching the fish you keep, determining their adult size, whether or not they require open space to swim, whether they consume a lot of food constantly and produce a constant stream of waste (herbivores), whether they need tankmates or do better without, etc., to determine how to stock the tank. If you keep the tank heavily stocked, like some will keep African cichlids so they won't be able to establish territories, then you will have to change the water quite frequently, perhaps twice a week. If you have one specimen fish and a few dithers, then you don't need to change the water so often. The 1" rule does not really enter into it much, IMO.

 

[fishbert]

Also depends on amount of and quality of filtration, number and type of live plants, how often you do water changes (to get rid of nitrate.) Also, rule only applies to established tanks to which you are slowly adding stock. Not a very good rule at all, in my opinion.

 

[fish_doc]

Has anyone considered that the 1 inch rule goes back to the stoneage?

Actually the practice is fairly recent. Even as current as the 1930's Fish were kept in bare bones conditions. A tank without lighting or filtration. With the current advancements with filters there is still much speculation on what works and what does not work. Undergravel filters is one such example on current technology that creates discussion. Some sware by them while others sware at them.
One thing is that we have learned a lot about is what it takes to keep fish alive and even then there are still many species that we don't quite understand what it takes.

 

[TankGirl]

One thing is that we have learned a lot about is what it takes to keep fish alive and even then there are still many species that we don't quite understand what it takes.

Right. That is why researching the particular fish you are interested in is so important. When I started in the hobby there was no Internet, so you had to go by what your LFS told you, or go to the library. Now we can look up species info from many different sites, and discuss optimum conditions before we purchase a fish.