Cory Breeding Help Needed!!

[Gillworthy]

Last year I purchased a couple Bronze Cory and placed them in a quarantine tank for 30 days. by the end of the 2nd week they where breeding and before they where out of quarantine their numbers had significantly increased. I then moved them into my 75 gallon with a school of silver dollars hoping this would stop the breeding or the Silver dollars would keep the population down. The water in the 75 gallon is harder as well. To my dismay the breeding is more active than ever and I woke up this morning to find eggs all over the back and side of the tank. I know have over two dozen Corys and exceeding the tanks capacity.  I've had Corys before and did not have this problem. Is there a way I can maintain a healthy environment for them and stop them from breeding???

[gardenman]

Fish pretty much live to eat and spawn. It's what they do. Happy, healthy fish will spawn if conditions are anything close to being right. Many fish spawn on a near daily basis, but the eggs and fry get devoured and the eggs and fry are so small as to be easily overlooked. If you have a sizable school of neon tetras, they'd be plopping out eggs almost nonstop. For most fish, the population is largely self-limiting as bigger fish eat smaller fish. Corys aren't especially tasty however, so they can avoid being eaten. (Even baby corys know to lock their fins out if something tries to eat them.) There are worse problems to have than too many corys. Other nearby hobbyists, pet shops, etc. may be very willing to take your excess.

[Gillworthy]

The last school of Corys I had was in a 100G with a couple very large Tin Foil Barbs. I suspect they, the Barbs, kept the population down. I occasionally had to extract adult Corys from a Barbs mouth with forceps.

I don't see Corys available in pet stores in my area. I am told this is due to the level of sodium in the local water supply however I do not know this for a fact. 

Thank you for your insight.

[Fish Folk]

Both of our LFS would take them once they reach a few centimeters and color up. Funny that many people struggle to get their corys to spawn when they want to!

[Gillworthy]

Well I will need to find a solution. I have never seen as many eggs as I have this time. There are hundreds of eggs. Each time there are more as the population increases. Possibly I could introduce a fish that will eat the eggs. Even if I find someone to take some now they spawn at an alarming rate. I over filter the tank they are in now so it will be a struggle for fry and this bothers me. I wish there was money it breeding them......

[mountaintoppufferkeeper]

I had a group of 6 pandas in a planted 55 one of the first water changes I noticed a free swimming fry. It pretty much went crazy immediately after that and they had grown to a group of 130 when I finally broke that tank down and moved everyone around. Once corydoras get going it can definitely be an issue. I feel your pain on that one it was so cool initially and then it was like an explosion of corydoras that no one wants to eat when they hatch out. If it were me, post panda cory learning experience, I would try a two pronged attack 1. add some more snails to the tank to hopefully eat eggs, and 2. if I were only interested in keeping the group a certain size I would attempt to catch the entire school so I could pull out the females. I would move the females and any extra males on to a store or friends or some other option. I believe I would try and make that school a bachelor group of only males in the amount that I chose for that tank.

[Andy's Fish Den]

Either something to eat the eggs or manually remove the eggs when they are laid.