# max number of fish for 20 gallon tank



## zachfishman (Jul 1, 2006)

Each tank will be different. You can definitely have many, many more fish in there. Just add them slowly and monitor your ammonia levels as the beneficial bacteria in your tank will have to catch up.
Example: my 10g is lightly planted, and heavily stocked with a 5" pleco, a 4" rainbow shark, 10 neons, 2 small danios, 3 platties, 2 cories, and 1 black molly (so much for the 1" per 1gal guideline). I have no filtration, just an empty hang-on powerfilter. I never have any detectable ammonia, there's enough bacteria in my substrate to take care of the bioload.


----------



## mr.gaboozlebag (Feb 22, 2006)

zachfishman said:


> Each tank will be different. You can definitely have many, many more fish in there. Just add them slowly and monitor your ammonia levels as the beneficial bacteria in your tank will have to catch up.
> Example: my 10g is lightly planted, and heavily stocked with a 5" pleco, a 4" rainbow shark, 10 neons, 2 small danios, 3 platties, 2 cories, and 1 black molly (so much for the 1" per 1gal guideline). I have no filtration, just an empty hang-on powerfilter. I never have any detectable ammonia, there's enough bacteria in my substrate to take care of the bioload.


Yes, but would you like to live in an apartment with a 19 people, some which get longer than the apartment were you are?


----------



## zachfishman (Jul 1, 2006)

Don't worry, just talking about bioload. There's a 40gallon for the pleco and shark when they get bigger.


----------



## jaimeallen (Jun 24, 2006)

zachfishman said:


> Each tank will be different. You can definitely have many, many more fish in there. Just add them slowly and monitor your ammonia levels as the beneficial bacteria in your tank will have to catch up.
> Example: my 10g is lightly planted, and heavily stocked with a 5" pleco, a 4" rainbow shark, 10 neons, 2 small danios, 3 platties, 2 cories, and 1 black molly (so much for the 1" per 1gal guideline). I have no filtration, just an empty hang-on powerfilter. I never have any detectable ammonia, there's enough bacteria in my substrate to take care of the bioload.


What I want would be maybe six more algae eating fish and or shrimp along with two small schools six or seven for each school (tetra or Harlequin variety). From what you are saying it sounds like it should be no problem. 

I 'am using a fluval 203 with a sponge filter and ceramic disc as my media. The middle cannister is empty.


----------



## yoink (Apr 21, 2005)

I'd put another oto or two, some cherry shrimp, and a few olive nerites. That should be enough algae crew. I have a twenty gallon that I like better with 10 black neons instead of 7 black neons and 7 neons. You should go with one species of schooling fish, it looks better IMO. Maybe some lower level fish such as cory cats or blue rams.


----------



## notropis (Sep 16, 2005)

I also like the single species school in my 20 gal tank with some lower level critters. As you can see from my sig I have a lot of fish in my tank, due to an unplanned breeding. Even though everyone seems to be doing fine I'm considering bringing some babies back to the lfs. It's just too crowded for them to really enjoy swimming around.


----------



## mr.gaboozlebag (Feb 22, 2006)

> Don't worry, just talking about bioload. There's a 40gallon for the pleco and shark when they get bigger.


What about when they get even to big for that?


----------



## trustbran (Jun 27, 2006)

definitly I agree that one type of schooling fish looks best...
I have a 90x45x45cm tank with 30 simulans(green tetras) and a 
algae squad which consits of ottos and cherries.......


----------



## jaimeallen (Jun 24, 2006)

Acutally What I 'am reading it is difficult to maintain two species that school due to tank size. They will not school well individually. One species in a tank makes for a tighter better school. Keeping a bigger fish that occupies the bottom of the tank such as maybe loaches or one Gourami as a perceived threat to the shoal will help maintain the school. 

I will only keep one school and I will be going with twelve Rummy nose tetras in my 20 long.


----------



## 2wheelsx2 (Jan 27, 2006)

mr.gaboozlebag said:


> What about when they get even to big for that?


They won't if it's a BNP or a rubber lip. BNP's get to 5" usually, 7 - 8" max for rare large ones. And Rainbow sharks also max out at 7". Two 7" fish in a 40 gallon is not overstocked no matter what rules you use.

Now if the pleco was a Gibbey or a common, then I would say he's in for some trouble.


----------



## notropis (Sep 16, 2005)

I'd love to see some pics when you get the fish in. Do you think you'll get a bottom/threat fish?


----------

