Can I keep alot of Xenotilapia species togheter ?
I wouldn't do that, not even in a 6 meter tank, not even in a pool.
the reasons are several.
first off, you get competition for the same place in the tank i.e. the sandy floor.
next: you can be quite sure that the most agressive, most active and toughest species will win the space, the most food, the best breeding spots.
some will be able to cope with the agression, but some definitely will not.
then there's the issue of species wich are very very similar in breeding, shape and behaviour. if you combine these the males can and do diusplay to the "wrong" females. in the least, this leads to stress and agression issues. worse: hybridisation can happen.
last: in the lake this simply doesn't happen! there are no spots where you can find for example 5 or 7 Xeno's all mixed up.
some will live near rocks (X papilio), others in the intermediate habitat (X spilopterus, X flavipinnis etc). others live in shallow water ( Enantiopus) while some definitely like the deeps ( X ornatipinnis, X sp 'Red Princess', X
bathyphilus......). in the wild all these fish will rarily if ever meet up!
say, you'd go for the more sandy biotope Xenotilapia's. there are several species in the trade here in the Netherlands. checked it out and I'm fairly impressed myself

Enantiopus melanogenys, E sp 'Kilesa', Xenotilapia sp "ochrogenys Ndole", X ochrogenys, X flanipinnis, X bathyphilus, X sima, X boulengeri, X ornatipinnis and X sp "Red Princess". of these some are even readily available in several different local varieties like the melanogenys and the flavipinnis.
in this impressive list already some combinations are too close:
-every combination of the same species from different locations. say E melanogenys 'Burundi' and E melanogenys 'Isanga'. or 2 flavipinnis varieties.
-Enantiopus sp Kilesa shouldn't be combined with E melanogenys. these 2 can and will crossbreed
-X sp 'Ndole' cannot be combined with X ochrogenys. similar reasons
-X ornatipinnis is very similar to X sp 'Red Princess'. I do not know if they can crossbreed, but the bodyshape and size is virtually the same....ask the experts on this one. but I wouldn't combine the Red Princess with anything that looks like it or any nasty sanddweller anyway.
-X sima is too similar to X boulengeri. also X flavipinnis looks a LOT like halfgrown fishes of these 2 species but has a LOT more character. Flavi's can kick "sima/boulengeri ass" so to speak.
-for the same reasons X flavipinnis cannot be combined with X ornatipinnis. been there, done that, doesn't work.
-X sp Ndole is another nasty. this one too kicks Xeno-butt from docile species, X bathyphilus, ditto, but a wee bit less nasty. still: stress will happen.
best go for just 1 or 2 species and get a very large group! much more rewarding IMO.
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