Dicrossus maculatus

[Randy or Deb Carey <carey@spacestar.net>]

A while back someone asked me about the water parameters of the spawning
success I've had with Dicrossus maculatus.  At that time I couldn't find
an entry in my log.  I've recently had more spawnings and would like to
share some info.

I currently have 3 females each leading very young fry.  A few weeks ago
another female was leading fry (of which I "harvested" a good number).
All successes have some common threads:

  * low to very low pH (low 5's to 3.6)
  * aged water, significant nitrates (how do you think the pH got that
low)
  * presence of other fish (tetras) but few enough for the female to
successfully keep them at bay.  (I've seen eggs in a tank without other
fish, but never any hatches.)
  * smallest tank was a 20 high, largest a 40 breeder.
  * eggs always on a flat surface
  * fry can't take bbs for a few days (perhaps this is why the successes
have come in aged water)
  * only 1 male with at least 2 females (however, I've just removed an
injured female because there was not enough territory for 4 females in a
20)
  * pre-spawn diet included live black worms and bbs.

The first successes came in tanks with undergravel filters, but in the
most recent success I have just found 2 females each guarding a "cloud"
in a bare bottomed 20 high.  I was shocked to read the pH at 3.6 and
even to find fry.  That 20 was meant as a holding tank while I worked
with three other maculatus set-ups.  I figured they wouldn't spawn if it
was that crowded.

My importer has found heavy female ratios once and heavy male ratios
later.  To combat the possiblity of skewed sexes, I am shifting the pH
from the low side to mid-upper 6's throughout the first month of life.
This apparently worked for Romer on Apisto's.

- --Randy

http://www.spacestar.net/users/carey/fishroom/