Cac spawning trigger?

[leamos]

My pair have been teasing me for the past few weeks, courting, checking out spawning sites, the male clears the livebearers to one side of the tank, then the male chases the female (normal i know) but then nothing, this repeats every few days. Been feeding frozen bloodworms, daphina, bs and live microworms. pH 7.2, using rainwater so softish water, temp 29 degc. 10% wc every few days and one 50% wc a week. Anyone got any ideas on getting these guys to spawn?

 

[dw1305]

Hi Leamos,
I'd just wait your water is very similar to mine, lots of live food etc. if the female goes missing for a couple of days, she will have spawned and be in her cave. If nothing happens I'd try adding a bit more cover,
have a look at ApistoBob's suggestions on "Dwarf Cichlids" web site.

I've found that A. cacatuoides is much better as a harem of 1 male and 2 or 3 females, despite the shops selling them as pairs. You may find also find that at that pH and temperature you'll end up with mainly male fry. I'm still struggling with m:f ratio for fry but at just over pH 7 I think 27oC should give you a fairly balanced sex ratio.

cheers Darrel

 

[Csababá]

Does ph or temperature affect more the sex ratio? In what exact ways?

 

[ste12000]

Romer did a detailed study on sex ratios being influenced by temp and PH in his book, cichlid atlas 1 by mergus...Its hard to find now but worth every penny of what you need to spend to aquire it...
Without giving everything away romer found that at a temp of 26c the average over a set number of spawnings was very roughly 50/50, lower temps(23c) produced more females, higher temps (29c) produced male heavy broods. Remember this is a average over several spawnings so it is still possible for a single spawn to have a skewed ratio..I would highly recommend the book, it is a Apistogramma keepers bible.

 

[leamos]

I've started using a small mirror(20min at a time max) to trick the pair into thinking that there is another pair in the tank seems to be working, the male's colours are more vibrant and his dorsal fin seems to be growing by the day! I re-arranged the tank a bit and added some large floating plants, the females been feasting in the mass of roots vailing sections of the tank, added 2 more spawning sites, making a total of 9 caves

 

[leamos]

Female came out for food just now and her colours have changed she gone darker and all stripes up, fins are almost as orange as the males (both orange-flash) and her underside has a faint bluey/green colour......so fingers crossed

 

[Csababá]

Thank you ste. I've never seen the most popular and recommended books around here. Maybe later. My country has a very low aquaristical interest/culture, I think.
Does the sex ratio fix when the eggs are laid or even later?

 

[dw1305]

sex ratio

Hi Csababa,
It's a bit of strange one in that supposedly the temperature after hatching is important.

Scientific reference is:
<http://www.blackwell-synergy.com/doi/abs/10.1111/j.1095-8649.1996.tb01467.x>

"Environmental determination of sex in Apistogrammai (Cichlidae) and two other freshwater fishes (Teleostei)
U. Römer 1 W. Beisenherz 1
University of Bielefeld, Department of Biology, Postfach 100131, 33501 Bielefeld, Germany
Copyright 1996 The Fisheries Society of the British Isles
KEYWORDS
Apistogramma • Cichlidae • environmental sex determination • pH • sex ratio • temperature
ABSTRACT
Environmental sex determination by temperature could be revealed significantly in 33 Apistogramma-species and in Poecilia melanogaster. In some, but not all, Apistogramma-species pH also influences the sex ratio, whereas neither temperature nor pH affect the sex ratio of Pseudocrenilabrus multicolor victoriae. The sex in offspring of A. trifasciata is determined within a sensitive period of about 30 to at least 40 days after spawning."

cheers Darrel

 

[Csababá]

Thank you Darrel.
Anyway, it was a kind of theoretical question since I have only 10 fries growing very slowly. So neither commercial nor breeder's purposes are available for me.
By the way, if I could find no other male/female, can I cross the juveniles later with their parents or is it nor recommended? I think crossing brothers and sisters leads to even more unsatisfied results. Am I right?

 

[ste12000]

If there are no obvious problems with the parents then breeding parent to son/daughter should cause no obvious problems if the fish are not already heavily line bred.. You idealy need to introduce new blood periodically but with careful selection its suprising how long you can breed siblings together for and still obtain good results.

 

[leamos]

quick update: feed the pair nothing but micros for 2 days and now the female has taken up residence in the male's cave, the male is quickly evicted whenever he goes in and only coming out for food. So things are finally happening:biggrin:

 

[Csababá]

Thanks a lot, Ste.

Leamos, any update, pictures?