Open to ideas

[viejo]

I am still having no success in getting a hatch out of my hemichromis 'cf. cristatus UL-1's' (avatar) & have ruled out so far- pH, water chemistry & flouride ( I thought for sure that this was it). Presently they are in RO water with a low tds & a pH that has been as low a 4 (presently @ 5.5), the temperature has varied from 78 to 85. Frequent water changes & a good diet (Live, frozen & dry). I have tried both pulling the spawn & leaving with the parents, no joy either way. I also had the same problem with Ramerizi but have had no problem with other soft water species such as F2 peruvian angels. It's a real puzzler. Oh yes, I also have had no hatching success with a proven pair of tilapia joka under conditions as described above.

 

[indyplanted]

I had a similar problem until I moved my A. pebas to a bigger tank. Female would lay eggs but not let male fertilize them. Just a thought?

 

[viejo]

I had a similar problem until I moved my A. pebas to a bigger tank. Female would lay eggs but not let male fertilize them. Just a thought?

The ova seem to be fertilized ( at least the majority of them). They just stubbornly refuse to develop or hatch. Presently the breeders are in a 40 breeder which should be plenty of 'footprint' for them. I have watched the males fertilize the eggs. We are talking several pairs here, which are all spawning.

 

[Mike Wise]

Certain heavy metals in small quantities (zinc, for one) dissolved in the water is known to stop development of eggs in trout. Maybe it is the same for cichlids? On the other hand, I can't see how they could be in R/O water.

 

[viejo]

Yes, I can't see much of anything getting thru the RO. I may just have to 'polish' it with a deionizer but somehow I suspect that it may be something else although I am rapidly running out of theories. I haven't tried UV sterilization and/or ozone yet but it is on the to-do list as is pulling the spawn & pre-treating with peroxide or another anti microbial/fungal agent.
Oh yes, I neglected to mention that the water has a good tannin content (peat & almond leaves).