CORYDORAS LOXOZONUS - Water for hatching

[cartouche]

Several months ago I referred about my unsuccessful attempts to breed Corydoras loxozonus. Today they started to breed on their own and I would like to know, what to do with the eggs, because it may be a rare event. I have read in the internet that raising the fry is not just easy
http://www.aquaristik.de/artikel/suss14.htm
and I wouldn't want to waste any bunch of eggs. I intend to use two sorts of water, 8,5 dGH+pH 6,5 and 4 dGH+pH 6,5.

I think it was Ian Fuller, who talked about his friend, who breeds this species quite often. Perhaps he could share some experience with us here.

[Coryman]

Cartouche,

I am not able to respond a soon as I would normally do because of other time consuming work and by now your eggs should have hatched and fry free swimming.

Not wishing to offend your integrity but did you think to read the sticky that I have written, detailing my recommended methods for hatching and raising fry.

Ian

[apistomaster]

Hi Cartouche,
I have followed your posts and noticed that you have stated you have been successful with many Corydoras species not reknown for their ease of raising the fry past their delicate larval phase of development. Whatever has worked for you in the past should be quite applicable to raisng Corydoras loxonus. I think a long as you are fortunate to have breeding stock that provide you with eggs you will soon overcome any initial difficulties as easily as you have with other species in the past.

I reviewed the cat-t-log info on this species but I am puzzled about the recommended maintenance temperatures. Suggested temps are about 22*C. Yet they seem to be found in proximity to Mikrogeophagus ramirezi which is very much a heat loving species. At what temperatures are your C. loxzonus breeding?

I just saw that my provincial LFS had six specimens of Corydoras loxonus which I was sorely tempted to buy but since they seem to prefer buying inferior fish from their wholesaler than those I raise right here in town in the same water, we are at something of an impasse. I wouldn't mind having them but Corydoras are not a profitable genera for me to breed. I have to get about $7.00 US or more per fish, wholesale price or I am spending more than they cost me to raise. I still breed some for personal pleasure.

[cartouche]

Fortunately, the eggs hatched perfectly in my tap water (8 dGH) - with a bit of HCl that I add to reduce my high pH 7,5-8 to 6,5. So the info on the German page must have been a pure mythology! In the softer water (4 dGH), hatching was obviously worse, but still, I have 40 pieces of fry out of 59 eggs. The larvae normally developed and the fry seem to be quite robust. I mixed them with several young Sterbai and Venezuela Black, and so far I haven't noticed a single lose. It is a relatively easy species to raise, I think. During the last days, I again noticed signs of courting among my 9 adult fish, so a new spawning is not excluded.

It is really a bizarre thing. I couldn't spawn them even with carp pituitary, I tried it unsuccessfully many times during the whole last year, and now, when I already intended to get rid of them, they start to spawn on theirselves!

Undoubtedly, improved composition of food (after a relatively poor winter, during which I ran out of my food reserves) played a key role here. However, I fed them with the same food during summer 2007, and they showed no signs of spawning activity. Or did just the improvement of food composition have the stimulating effect?

NOTE: The temperature in my tank with Loxozonus is not particularly high, about 22,5 C. It is true that they are not the most expensive species, but it is an interesting fish that I like. I take them as a certain sort of "refreshment" in my fish house.

[cartouche]

Cartouche,

I am not able to respond a soon as I would normally do because of other time consuming work and by now your eggs should have hatched and fry free swimming.

Not wishing to offend your integrity but did you think to read the sticky that I have written, detailing my recommended methods for hatching and raising fry.

Ian

I would like to note that not all Corydoras hatch at "normal" water parameters. And even the same (allegedly the same) species. This is what I was afraid. In the past I had a breeding group of Corydoras duplicareus, whose eggs only hatched within a very narrow water parameters (4-7 dGH). Then I bought a new group and their eggs hatch within a much wider chemistry. In fact, now it is much easier, because I don't have to check any water parameters at all. Hence I think that many "species" actually consist of very different local populations with different demands.

[apistomaster]

I agree with you that the same species from different populations can be raised best in different conditions.

I liked the C. loxonus and I was tempted but I only have so much space. Still, I continue to raise the dwarf Corydoras habrosus and C. hastatus simply because they are fun. C. hastatus is actually rather rare in the US. It took me decades to finally receive them instead of C. pygmeus which is still often sold as C. hastatus. I think they are worth more as a fish to sell because the access to the real C. hastatus is generally so poor in this country.