Can I do this? Or will they interbreed?

[captmicha]

At some point in the near future, I'd like to breed the dwarf cory species. I don't happen to have 3 extra tanks laying around for each different species. If the tank is big enough, can I put C. pygmaeus, habrosus and hastatus all in together in the same tank?

Or will they interbreed?

These species aren't known for eating their eggs, if I remember what I read correctly. Can some one verify that for me please?

[MatsP]

Why not pick one species, see if you can breed those, then when you've "ticked that box", switch to another species? If nothing else, a larger group of one species looks better when you see them in the tank.

--
Mats

[pleco_breeder]

I've never attempted spawning pygmaeus without pulling the breeders, but did have the occasional fry show up in a heavily planted tank with habrosus when I kept them.

I've been trying to spawn hastatus without pulling the adults for a couple months now, and have had no success. I just recently pulled 4 pair from my colony to condition separately and pull eggs in the more traditional manner as I got tired of waiting on them to figure out what I'm doing. They're easy to spawn, but IME have a strong inclination for eating eggs.

Likewise, I have to agree with MatsP that a large group of a single species looks much better as they school around the tank.

Larry

[rhibear]

I have pygmys and habrosus spawning in the same tank without any problems.

[apistomaster]

Corydoras hastatus and to a lesser extent, C. habrosus can be very productive in colony style breeding tanks. Hybrids are of no concern between the 3 dwarf Corys because they are incredibly unlikely.
The colony breeding of C. hastatus will begin slowly if you start with only 10 or 12 fish. I had to start over but I still had 50 so they have rebounded to well over 100 and as soon as i have about 200 I can sell them and they are replaced at about the same rate as they get harvested. I allowed my colony to almost disappear but just began rebuilding it 8 months ago. It will soon reach full productivity and I will resume selling C. hastatus later this summer.
There are some things that can promote better results in colony breeding of C. hastatus. C. habrosus lays fewer and larger eggs so they do not build as large a colony as quickly as hastatus.

I use a 20 Long. There is a mat of Hornwort growth below the surface. Java Moss in large clumps works about as well.
They breed better if they are kept in soft water and a pH close to 7.0, water temps 82*F to 84*F is what I use.
If you use fine sand on the bottom then provide piles of hollow ceramic bio-media. Between the plants and the little hollow tube caves nearly all the fry will survive but you must feed them live newly hatched brine shrimp for the fry and larvae and it helps the adults be more productive. An alternate to hollow media piles you can use fairly coarse grained, smooth particle shape fine gravel. Beware that when you vacuum the coarser substrate you must check the bucket before throwing away the water. My friend uses the coarse substrate method and I don't but he found 37 fry in the 5 gal buck of water he removed while vacuuming the substrate and returned them to the colony. The minute larvae will find refuge among the interstices of the substrate particles as well as the plants. I change at least 3/4 of my water about every 3 to 5 days. A massive spawning frenzy will occur after every water change.
I try to keep the TDS between 40 and 60 ppm. Productivity will be much higher in soft water than med hard to very hard water. I can not over emphasize the importance of the at least twice daily live bbs feedings. You are feeding the fry and adults at the same time. The adults will need some Grindal worms, Black worms and earth worm sticks as part of their diet. Their small fry also eat earth worm sticks but brine shrimp nauplii are essential. You can use mikroworms for variety but the fry will not thrive on a diet of mostly mikroworms. Grow is rapid and males as young as 4 months will participate in breeding frenzies.
It is also perfectly fine to promote a coexisting colony of Cherry Shrimp. They do no harm to tough Cory eggs but they do help keep them clean of debris during their 4 to 5 day incubation period.
I use Azoo Oxygen Plus Bio-Filter #6 X 2 per tank and an air stone. One filter is used with the traditional airlift while the other is powered by a MaxiJet 600 Power head at 160 gph. It happens that this power head's extension tube fits the filter directly without using the airlift on the one. The MaxiJet 400 is also satisfactory. The use of sponge filters prevents the loss of any fry and live bbs as often happens with other filter designs. The C. hastatus really do best when there is a brisk current and highest dissolved O2 levels. I am able to maintain about 200 C. hastatus in a 20 long when it is set up as I have described and the population will remain stable even if you sell a 150 fish from the colony a year. Regular harvesting is necessary once you have reach a total population of 150 and up. Otherwise they will become too overcrowded and are subject to a population crash. Live foods are essential for good production.
Here is the info about this sponge filter: Pay no attention to the size of tank they recommend. 2 in a 20 to 40 gal is adequate. Not one for a 110 gal as they claim.
http://www.fosterandsmithaquatics.com/p ... 41&catid=3