Fairy Cichlid (N.Brichardi) and Malawi

[tetrin]

also, the 5" max size is listed usually for the dominant male. adult females are 1/3 smaller than males, setting them at around 3-3.5 inches. and i'm guessing the subdominant male won't be allowed to attain full size too (or rather won't attain full size).
that leaves 12 adults at around 40 inches.

 

[greenmaji]

I personaly would never recomend having 40inchs of fish in a 30 gallon tank.. that said.. I do think the females get bigger then 3-3.5" though...

 

[Fishyfanatic]

It is good to overstock Mbuna tanks mainly for aggression. I would put a max of 35 inches in a 30 gal tank though.

This is granted that you keep up with weekly water changes and maintain good water quality. Ie: Nitrates below 30.

There was a member who used to frequent the site (wonder why he left, haven't seen him for months) that kept 25 guppies in a 10 gal tank and they were happy as can be. He did daily 50% water changes which allowed for the overstocking.

 

[greenmaji]

my bad..
fishbase.org says the maximum size is 8.1cm.. or 3.19inches..
Yellow Lab. Profile on fishbase.org