I have two pairs of aph. australes in a planted ten gallon tank and a couple of people in my area are interested in trading eggs with me. My pairs produce well, but I find the eggs have a terrible fertility rate. It doesn’t seem to matter how I try to keep them, I almost always lose at least half to fungus before getting them all the way to hatching. Most recently, I’ve tried water incubating with a bit of methylene blue. I’ve already lost eight eggs to fungus just in this first week. For my own purposes, this doesn’t matter so much but I’d like to be able to make exchanges with other hobbyists and get them some viable eggs. Any tips appreciated!
The pH of their water is 7.6 and the GH is around 50ppm. Not sure if that helps but I might as well include it.
Hi Andrea,
How old are the fish? Young fish may not be fully fertile.
Alternatively, it could be a water quality issue. If the water is dirty, with too many bacteria, this can cause egg death. If the eggs die within 3 days of collection then this could be the problem—or that the eggs weren’t fertilized.
50 ppm is quite soft and there might not be enough Magnesium in the water to quickly harden the egg against bacteria, so you could add a little epson salts to the water.
What I would first do is add a little tea. Brew a cup of tea as per normal and add just enough to tint the water slightly brown. This seems strange but it does work to improve fertility or protect the eggs. I am not sure why.
When reading Wolfgang Eberl’s book on the cameronense group, one of the co-authors mentioned that they pull the mops and leave them to sit for 15 minutes before picking eggs so they have time to harden. This piece of advice has worked very well for me when I had similar issues of eggs dying (for both non-annuals and annuals!).
Good luck
Hello Tyrone,
Thank you! The fish are probably just under a year old and this infertility is actually a recent issue so I know they are capable of producing fertile eggs. I was thinking the soft water is the issue but I wasn’t sure. The person who sold the fish to me said they do best when the hardness is below 100ppm and I’ve gradually dropped the hardness of the water on purpose so I think I took it too far.
When you say adding tea to the tank, is there a specific tea you have in mind? Would red rose orange pekoe be okay? and do you mean to add some to the tank with the fish or to the water where the eggs incubate?
Thanks so much for your input!
Hello,
I have used Redbush (rooibos) and regular English Tea before. I don’t know about the Pekoe tea… I just add it to the aquarium. The fish seem very happy having a cup of tea. This is a trick I learnt from BKA members.
Australe are soft-water fish and I have had no issue breeding them in soft, acidic water. I think soft and acidic might be the key issue. Soft and alkaline might be an issue.
Good luck!
Hello again,
I’ll try some regular black tea, just asking about the pekoe since I have some on hand.
I’ve tried so many things to lower my pH and it just never seems to budge. sphagnum moss, alder cones, indian almond leaves all seem to have very little effect on my pH and I’m reluctant to use chemical alternatives. I was under the impression that distilled water would help with this as well as reducing hardness but it doesn’t seem to have had that effect. I just end up with softer, still slightly alkaline water.
It’s funny you should say that because I was getting such awful results water incubating them that I did almost exactly what you just recommended! Many more eggs made it to hatching but my misfortune continued because most of them turned out to be belly sliders. I’m wondering now if that has anything to do with the fact I kept the peat close to dry instead of having it as moist as you described?
Since that hatch, nothing I’ve read has mentioned the condition of the peat as a cause for belly sliders so I’m just throwing that out there. What I have read is that the oxygen available in the hatching water and the amount of time you let the eggs go before wetting them seem like the most important factors. Also these are chocolate australes I’m dealing with. To your knowledge, does that mean anything in terms of inbreeding?
I’m not sure about any relationship with the peat being to dry and belly sliders but it would be an easy hypothesis to test. There have been a few importations of chocolate (naturally occurring) australe so I would assume there is less chance of inbreeding with these.
I’m lucky enough that my pairs are producing tons of eggs so I get a lot of chances to work out my mistakes and try new things. A few tweaks I’ve made already seem to be giving me better results. I don’t know why I immediately jumped to the conclusion that the fertility of the eggs was the problem, I’m pretty sure now the issue is that I’m still learning the basics.
I was surprised to learn these are the more naturally occurring colouration! Seems like a pretty big strike against the idea of infertility from in-breeding.
Actually the sport orange australe have been in the hobby for years so I doubt there is a large amount of inbreeding issues. I would think it’s more how the eggs are handled and the fertility of the individual specimens.
