Runts
 

I have a collection of Mbuna fry, from 6 or seven different spawnings.
about 25 total. The largest have grown to about an inch and a half. Even
the largest from the latest breeding have reached an inch. There are 3
little fish, however that refuse to grow. I've watch closely at feeding
time for the last few weeks, and they seem to be eating more than enough,
yet they're still only 1/2" long. I have WAY too many of them crammed into
a 20 gal tank, I know. I was hoping to see some adult coloring before I
take them down to the LFS. Their Father was M. estherae, and I Think their
mother was G. acei. The original fry is about 3" now, and a very pale ,
almost albino, pink. He has thin, blue "eyeshadow". The others seem to be
following the same trend.

Anyway, are runts common, or could other conditions be affecting their
growth?


P.S. I can't say for certain if these 'runts' were from the last breeding,
but it might be worth mentioning that the mother died within weeks of giving
birth, and the father about a month and a half later.

Ed VanDyke wrote:
I have a collection of Mbuna fry, from 6 or seven different spawnings.
about 25 total. The largest have grown to about an inch and a half. Even
the largest from the latest breeding have reached an inch. There are 3
little fish, however that refuse to grow. I've watch closely at feeding
time for the last few weeks, and they seem to be eating more than enough,
yet they're still only 1/2" long. I have WAY too many of them crammed into
a 20 gal tank, I know. I was hoping to see some adult coloring before I
take them down to the LFS. Their Father was M. estherae, and I Think their
mother was G. acei. The original fry is about 3" now, and a very pale ,
almost albino, pink. He has thin, blue "eyeshadow". The others seem to be
following the same trend.

Anyway, are runts common, or could other conditions be affecting their
growth?


P.S. I can't say for certain if these 'runts' were from the last breeding,
but it might be worth mentioning that the mother died within weeks of giving
birth, and the father about a month and a half later.


Two things could be happening. These fish are hybrids and the offspring
may have inherited different sets of genes from the parents. You could
be seeing natural variation in the hybrid offspring. Hybrids tend to
have a lot of variability.

Second, you could have simply stunted their growth by cramming WAY too
many in a 20 gal tank.

soapbox I'm personally not in favor of raising and selling hybrid
fish. I think it makes it harder to keep fish with clean genotypes in
the hobby for breeding and maintaining species that are hard to find in
the wild. /soapbox

--
__ Elaine T __
__' http://eethomp.com/fish.html '__

I have to agree with you in principle regarding hybrids in the store. It is
hard to fish a nice purebred fish. There is definitely apprehension on my
part for doing it. In this case the store has tanks FULL of hybrid mutts.
For many fishkeepers, these fish are perfectly good pets. Unless you want
all identical fish, or completely diverse genus', they're going to breed.
And let us not forget, there is no creature on earth more loveable, more
loyal, than the mutt.


--
"The task is not so much to see what no one yet has seen, but to think what
no body yet has thought about that which everyone sees."

Schopenhaeur (1788 - 1860).


Two things could be happening. These fish are hybrids and the offspring
may have inherited different sets of genes from the parents. You could be
seeing natural variation in the hybrid offspring. Hybrids tend to have a
lot of variability.

Second, you could have simply stunted their growth by cramming WAY too
many in a 20 gal tank.

soapbox I'm personally not in favor of raising and selling hybrid fish.
I think it makes it harder to keep fish with clean genotypes in the hobby
for breeding and maintaining species that are hard to find in the wild.
/soapbox

--
__ Elaine T __
__' http://eethomp.com/fish.html '__