Corydoras hastatus-"Natural Breeding Set Up."

[apistomaster]

I thought some might find my method of raising Corydoras hastatus interesting.
I began with ten specimens and set them up in a 20 gallon long, 12 X 12 X30 inches.
The bottom was covered with a layer of Eheim Ehfi-mech hollow ceramic biological filter media.
It is filtered by an AquaClear 50 with the intake covered with a sponge pre-filter and there is also an air stone running.
The tank has a heavy growth of Ceratophyllum demersum(Hornwort) which fills the top six inches of the water column.
Diet: Live Black Worms and Earth Worm Sticks.
Other fish: Sturisoma fry.

The Corys go through a spawning frenzy shortly after each of two weekly 75% water changes. The pH is 7.4 and the T.D.S. runs ~340 ppm. Just my tap water is used along with Prime added prior to topping off. I don't bother with aging the water.

I have had them set up this way for four months and I now have a school of ~50 Corydoras hastatus but the numbers continue to increase.. The fry join the school when the are about 1/4 to 3/8 inch TL; basically as soon as they have taken on the typical adult color pattern.

The eggs are laid everywhere but most are placed among the needle-like leaves of the Ceratophyllum. The newly hatched larvae and very young fry live on the bottom among the many hiding places provided by the Ehfi-mech hollow tubes. They stay there as long as their pattern is still mottled and ill defined. I do not feed the fry specifically. They eat whatever they find that is to their liking and I do allow a little detritus to accumulate which is loaded with rotifers and various Slipper animacules when a sample is examined under my microscope.
The Sturisoma fry coexist with the Corydoras of all age groups and may help round out the ecology that provides the fry with their first foods.

Not a high intensity breeding project but a fun one. It has allowed me to study the Corydoras hastatus life cycle and natural behaviors. One surprising observation has been just how early the newest members of the school begin joining in the spawning behavior. Much sooner and at a much smaller size than I would have predicted.
I have done the same with my Corydoras habrosus except the set up is newer and I only have about 12 detectable fry resembling miniatures of the adults.

[Carp37]

wow, that is interesting. I've been after hastatus in the UK for a while now with no success, but eventually got hold of 12 pygmaeus in a Catfish Study Group auction, 2 of which died in the first week but 10 of which have survived- I wonder if these would behave similarly.