Question on the 1 inch of fish per gallon rule..
- Thread starter cephei
- Start date
Study and research the fish you want to stock and then look at the recommended tank size. You actually need to be more concerned with the "footprint" of a tank than it's total volume.
Example: I have 6 fish that when fully grown are approximately 4 inches. 6X4=24 inches (20 High) - no good. Reality says I need a 55 gallon 48X13X21 or possibly a 40 breeder 36X18X17. Where one has length the other has width. Then you must consider the living/swimming level. Top swimmers, mid-level or bottom.
At present I have a 90 gallon (48X18X25)with 3 fish in it. a 4"(full grown), a 12"adolescent, a 10 adolescent. When all are full grown - 4", 15(?)", 24" = 43" and the smallest possible tank "might" be a 75 gallon (a 75 is 4" shorter than a 90). The difference of 15 gallons of water makes a huge difference in the health of the fish that are housed in it. By the same token, I have a 10 gallon with 22 full grown 1.5-2.5" fish in it. But because they swim all over and reside in no one level it works out well.
There is no stunting of any of the fish I have nor ammonia in the tank. The bio-loads are appropriate for the fish stocked regardless of size. (Nitrate is 20-30ppm Ammonia and Nitrite = 0). There are no super filters on the 10 as is integral with the hood like Eclipse (300L/H) and the 90 has 2 filters on it (900gph)
Just ask for recommendations when in doubt and bigger is better than too small of filter or tank.
Example: I have 6 fish that when fully grown are approximately 4 inches. 6X4=24 inches (20 High) - no good. Reality says I need a 55 gallon 48X13X21 or possibly a 40 breeder 36X18X17. Where one has length the other has width. Then you must consider the living/swimming level. Top swimmers, mid-level or bottom.
At present I have a 90 gallon (48X18X25)with 3 fish in it. a 4"(full grown), a 12"adolescent, a 10 adolescent. When all are full grown - 4", 15(?)", 24" = 43" and the smallest possible tank "might" be a 75 gallon (a 75 is 4" shorter than a 90). The difference of 15 gallons of water makes a huge difference in the health of the fish that are housed in it. By the same token, I have a 10 gallon with 22 full grown 1.5-2.5" fish in it. But because they swim all over and reside in no one level it works out well.
There is no stunting of any of the fish I have nor ammonia in the tank. The bio-loads are appropriate for the fish stocked regardless of size. (Nitrate is 20-30ppm Ammonia and Nitrite = 0). There are no super filters on the 10 as is integral with the hood like Eclipse (300L/H) and the 90 has 2 filters on it (900gph)
Just ask for recommendations when in doubt and bigger is better than too small of filter or tank.
i think it depends on the types of fish u want. if u want hyper active fish or territorial fish, then u'd need a bigger tank to accomodate them. if u have tetras, which like to be in schools, then u can fit more of them into the same amount of given area. some ppl also take into account how messy a fish is. i dont like going by that "guide" because u can over filtrate like mad in a tank, but it doesnt make a tank any more suitable. so i stock my fish based on each species' individual life style.
I was out of sorts when I stocked my tank & the stocking deal still confuses me.
I have a 46 gal bowfront. Theres 2 Angels, 1 Blood Parrot, 2 Coris, 2 small Placos & 3 Raffaels (who never come out of the caves. Everyone gets along fine with the exception of an occassional tift caused by the Parrot. My water was cloudy when I first got the tank cycled & I was told maybe I was feeding too much flake. Ive since switched to mostly frozen brine & bloodworms.
My 15 gal has 2 mollies, 1 betta, 2 coris and 1 placo. Its always a nice clear tank.
I have no idea if the big tank is considered over stocked...but it seems to be ok.
I have a 46 gal bowfront. Theres 2 Angels, 1 Blood Parrot, 2 Coris, 2 small Placos & 3 Raffaels (who never come out of the caves. Everyone gets along fine with the exception of an occassional tift caused by the Parrot. My water was cloudy when I first got the tank cycled & I was told maybe I was feeding too much flake. Ive since switched to mostly frozen brine & bloodworms.
My 15 gal has 2 mollies, 1 betta, 2 coris and 1 placo. Its always a nice clear tank.
I have no idea if the big tank is considered over stocked...but it seems to be ok.
Pick out the fish you like and then come back and ask for help from there would be my suggestion
Plecos can get quite large, too much for a 46 depending on variation. Common plecos get to 24". Saying "small" isn't a very good descriptor. It matters which pleco you have. Parrots are usually better off in a 55 for the swimming room as well as territorial needs.
It was never really a rule, but a suggestion that was made a very long time ago when filtration wasn't what it is now and people never did water changes except when they completely tore the tank down to "clean" it.
The part of the suggestion that is always left out was something assumed; "USE COMMON SENSE!"
You're not going to put a 10" fish in a 10 gallon tank. Sure, it's an inch per gallon, but it doesn't make a lick of common sense to do so.
I like to use what I call the 10x method. Take the max length a fish can grow and multiply it times 10 (10x). The result is the MINIMUM tank size in gallons. i.e. A fish gets to be 9" long then 9 x 10 = 90 gallons.
You can go one step more and check to see if you have enough surface area for your fish and multiply the length x width of your aquarium of choice.
i.e. a 90 gallon is 48 x 18 = 864
Take that result and divide it by the max length of your fish. i.e. 864 / 9 = 96
There's a 96% chance that I'm correct in putting a fish that has a max length of 9" in a 90 gallon tank.
Make sense?
The part of the suggestion that is always left out was something assumed; "USE COMMON SENSE!"
You're not going to put a 10" fish in a 10 gallon tank. Sure, it's an inch per gallon, but it doesn't make a lick of common sense to do so.
I like to use what I call the 10x method. Take the max length a fish can grow and multiply it times 10 (10x). The result is the MINIMUM tank size in gallons. i.e. A fish gets to be 9" long then 9 x 10 = 90 gallons.
You can go one step more and check to see if you have enough surface area for your fish and multiply the length x width of your aquarium of choice.
i.e. a 90 gallon is 48 x 18 = 864
Take that result and divide it by the max length of your fish. i.e. 864 / 9 = 96
There's a 96% chance that I'm correct in putting a fish that has a max length of 9" in a 90 gallon tank.
Make sense?
Nolapete: The Common Sense method is the best. Unfortunately Common Sense is extremly uncommon.
The 10X method actually seems very good and I cannot think of any common exceptions at the moment.
Forever is a long time and maybe the Hobby will change so that a rule can work for those looking to quantify fish keeping. For the moment no rule is commonly used. The old rules that are spread around may have made sense a long time ago but the Hobby has changed a lot for a lot of folk and nothing takes the place of experience, which is tough on the fish, plants and etc. but look at the gains in the salt water side in just a few years. The difference in attitude from Europe to here has been shattering to a lot of old commonly accepted ideas.
The 10X method actually seems very good and I cannot think of any common exceptions at the moment.
Forever is a long time and maybe the Hobby will change so that a rule can work for those looking to quantify fish keeping. For the moment no rule is commonly used. The old rules that are spread around may have made sense a long time ago but the Hobby has changed a lot for a lot of folk and nothing takes the place of experience, which is tough on the fish, plants and etc. but look at the gains in the salt water side in just a few years. The difference in attitude from Europe to here has been shattering to a lot of old commonly accepted ideas.
The 10x rule tells you the minimum tank size for a fish, but doesn't indicate total stocking levels, which the 1" rule claims to do. Unfortunately, as pointed out here, it's complete bunk because it's based on a bizarre 1 dimensional universe somewhere where biomass is proportional to length.
I think that 10x rule is for single large cichlid i suppose since i saw a flowerhorn in your avatar. If i am to house 10 cardinal tetra, maximum size of cardinal tetra = 2 inch x 10. That will be 20 gallons for one cardinal. For 10 cardinal, do i have to muliply with 10, like 10x20 gallons = 200gallons for 10cardinals. Isn't it a little large for 10 cardinals. But i agree to always understock. It's far better than overstocking.
