[im2smart4u]

I have 4 Xystichromis sp. "Blue Fire Fin" and 6 Odessa barbs that need a new tank. They are currently in a 25 gallon with a pair of ancistrus and a couple of otos. They seem to be doing fine, but would probably like more room. I would also like to fill out the school of Odessas to at least 10 or 12.

The tank I have been considering putting them in is a 40 breeder. The question I have is, how deep should the water be for them. I would like to setup the tank as an open top, maybe even do a riparium. I don't like the idea of the water level being close to the top, though, as that makes it more likely for the fish to be able to jump out. So, would it be okay to have the water level at around the 12 inch mark? With approx 2 inches of substrate, that would only be 10 inches of water. Is that enough? I have read how fish like angels need tall tanks (I have read at least 18 inches, preferably more), since they are tall fish, but I haven't see much on how deep the water for other fish should be. Is there a rule, like so many times the body height of the fish, or is it just guesstimation?

 

[im2smart4u]

Does anyone have any opinions on this? How shallow of water would you, or have you, kept fish in?

 

[theloneplant]

Generally, fish that aren't tall just need enough room to swim around. Most fish tend to stay in specific areas in the tank due to their nature. Top dwelling fish like hatchets stay at the top of the tank's height, mid level fish like your barbs like to stay in the middle, and grazers like your ancistrus and otos stay on the bottom.

One way you can tell where a fish stays is the direction their mouth is turned - top dwellers have an upward facing mouth, mid level have horizontal mouths, and suckers have a downward facing mouth. If your tank is long and short, fish will realize that they can't comfortably fit in one area of the tank since they wont have room and they will spread out along the tank.

Basically, you only really need to worry about tank size, not height unless you're trying to keep tall fish.

 

[reignOfFred]

If the barbs are not sharing the tank with fish that prefer different levels of the tank then the short tank will not be a problem - there is no point, say, in keeping mid and top dwellers in such a tank since with a lack of height they'll just use the same area anyway, given there isn't really a middle level. Otherwise fish swim mostly horizontal and so height is the least important aspect of a tank with exception to unusually tall fish.

 

[Sharkfood]

A 10 gallon tank is only 12" tall.