Mach,
I have found that P.mellis are particularly photoperiodic in their breeding
and by controlling their day-night cycle to about 14 hr light/10 hr dark and
keeping them well fed you can increase their egg productivity.
If the tank is in a room that must be used during the "night", cover it with
a black plastic drape to keep out ambient light and provide a separate tank
light, inside the drape, that is controlled by an automatic timer.
However, it hasn't seem to work with the popondettas. I still thing it was a
change in barometric pressure and they probably think it is the beginning of
the wet season particularly seeing that we haven't had a wet season over
here this year. Temperature and photoperiod no doubt also has some effects.
Maybe it just a matter of getting all of them in sequence. In the wild there
is usually a drop in temperature at the beginning of the 'wet' plus an
increase in daylength. What we need to do is get all the weather readings
for their breeding time in the wild.
Adrian.
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Adrian R. Tappin
"Home of the Rainbowfish"
http://www.ecn.net.au/~atappin/home.htm
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