<a href=showthread.php?s=&postid=11437302#post11437302 target=_blank>Originally posted</a> by marc price
i read somewhere that derasa are fast growers up to a point and then thicken the shell adding mass (girth) over length.
that is true of all clams, once they reach sexual maturity their growth rate slows.
<a href=showthread.php?s=&postid=11437302#post11437302 target=_blank>Originally posted</a> by marc price
additionally all things being equal how would the growth rate of t. maxima (which max. out about the same size as t. squmosa), compare?
T. crocea's grow between 1/2" - 1" per year
T. maxima's grow between 1" - 2" per year
H. hippopus grow between 1 1/2" - 3" per year
T. derasa's grow between 2" - 3" per year
T squamosa's grow between 1 1/2" - 3 1/2" per year
T. gigas grow between 1 1/2" - 4 1/2" per year
to save any confusion, i just posted them all.
<a href=showthread.php?s=&postid=11437302#post11437302 target=_blank>Originally posted</a> by marc price
so at around 8" - 9" would t. squamosa grow to +14" in two years vs. a similar sized derasa four in an exponential so on and so on?
derasa's and squamosa's have very similar growth rates and the sizes you are talking about are close to maturity. it would be very hard to predict their sizes because there are so many variables. i would guess that it would take both closer to the 4 years to go from 9" - 14".
<a href=showthread.php?s=&postid=11437302#post11437302 target=_blank>Originally posted</a> by marc price
and not to go off on a tangent but about what size do they begin to spawn and at what frequency?
this is going to obviously vary by species as well as individual clam and tank conditions. hopefully they never spawn in our system, spawning in the wild is brought on by lunar cycles and whatever else mother nature uses. usually spawning in our systems is a survival instinct ( clam out of water for to long or changing parameters etc ... ), when something goes wrong the clam tries to reproduce to continue the species.