I've seen photos of them up to about 10".
They come from soft, tannin rich waters with a pH between 5.5 to 6.8, prefer fine sand although, they are also found around pebbled littered fast flowing stream areas.
Being rheophillic, housing them with slower flow species like Heros might present a stress problem for one or the other.
Crenicichla regani, could be a good choice though, as they prefer the same type low pH, soft, tannin rich water, and also inhabit fast flow areas (although when in those ares, tend to hug the banks where flow is less strong).
This could easily be achieved running a power head with a current pushing the length but leaving the other half (eg back width of the tank) more tranquil.
They come from soft, tannin rich waters with a pH between 5.5 to 6.8, prefer fine sand although, they are also found around pebbled littered fast flowing stream areas.
Being rheophillic, housing them with slower flow species like Heros might present a stress problem for one or the other.
Crenicichla regani, could be a good choice though, as they prefer the same type low pH, soft, tannin rich water, and also inhabit fast flow areas (although when in those ares, tend to hug the banks where flow is less strong).
This could easily be achieved running a power head with a current pushing the length but leaving the other half (eg back width of the tank) more tranquil.
