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[If you want a trip down a "NERM hole" . . . here you go!] Spawning Report: Corydoras Aeneus (Bronze Corys) We've successfully finished our 30 days with a small batch of corydoras aeneus (11 fry). Guess this will be the last BAP submission for 2020 for us. Learned a lot with this project. Took a year of growing the Corys bought from our LFS, and a solid 8 months mounting up failures to figure out how to raise them. We're raising up a larger batch of fry behind these (ca. 20-25). VIDEO JOURNALS (1) Eight months ago . . . setting up a dedicated Cory breeding tank (2) Nov. 20, Cory eggs pulled (3) Nov. 22, Cory fry free swimming (11 fry counted) (4) Nov. 30, Fry growth and updates (5) Dec. 7, Two-week Journal - Chemistry Discussion (6) Dec. 11, Update and New Batch of Fry following up behind Our BAP batch (7) Dec. 24, Cory fry BAP graduation - adding fry (11) to adult breeding tank PVAS BAP SPAWNING REPORT 24 December 2020 SPECIES Corydoras Aeneus Bronze Corys REPRODUCTION Method of Reproduction: Egg Layer Number and Gender Distribution of Parents: Eight Adults, Possibly only 1-2 Males Origin of Parents: Tank Raised (Purchased from LFS) Approximate number of fry: ca. 11 Date of Birth: Free-Swimming (11/22/2020) Number of Fry at 30 Days: 11 AQUARUM CONDITIONS Spawning Tank Size: 20 gal. long Spawning Tank Water Source: town / city water Spawning Tank Water Changes: 30-50% 1x per week / bi-weekly Spawning Tank Filtration System: Two sponge filters Spawning Tank Temperature: 78-degrees Farenheit Spawning Tank pH: 6.0 (water changes cause fluctuations up, but it always drops) Spawning Tank KH: Unreadably low (tap water is ca. 4 dKH, ca. 71.6) Spawning Tank Ammonia: 0 ppm Spawning Tank Nitrite: 0 ppm Spawning Tank Nitrate: ca. 30 ppm Note: This tank has experienced a recent pH crash due to humic acid buildup from leaf litter decomposition and alder comes. We removed most the leaf litter and cones, and have been monitiring it’s chemistry. Specimen Container: 1/2 gal. Lee’s large specimen container Specimen Container Water Source: Bottled (RO) water Specimen Container Water Change: 16-32 oz. / day until sponge filter added after 2x weeks Specimen Container Filtration: None, just air line for 2x weeks; then small sponge filter added Specimen Container Temperature: ca. 80-degrees Fahrenheit Specimen Container pH — ca 6.0 (due to use of RO bottled water) and catappa leaf litter Specimen Container GH — Hard to determine . . . very low Specimen Container Ammonia: actually Ammonium - can be very high, 0.5-0.8ppm) Specimen Container Nitrite: 0 ppm (after sponge filter added) Specimen Container Nitrate: 40-80 ppm (very high) Note: Specimen Container readings taken after period without water change DECOR & ENVIRONMENT Spawning Tank Live Plants: Pothos (roots only), Cryptocoryne Parva Spawning Tank Caves or Similar Hiding Places: Rocks from stream (boiled before adding), wood Spawning Tank Substrate: Fine white stone (looks like coarse sand) Spawning Tank Lighting Type and Timing: LED, 5,000 K, filtered through diffuser, ca. 14 hrs / day Specimen Container Live Plants: None; only catappa leaf litter and alder cones Specimen Container Caves or Similar Hiding Places: None until sponge filter added Specimen Container Substrate: None; again, only catappa leaf litter and alder cones Specimen Container Lighting Type and Timing: LED, 5,000 K, filtered through diffuser, ca. 14 hrs / day FEEDING Food Fed to Parents and How Often: 2x / day. Frozen Blood worms, Bug Bites flake food, wide variety of flake mix - Omega One, Kelp Flakes, But Bites Tropical Blend; live baby brine shrimp Food Fed to Fry and How Often: 2x / day. Live baby brine shrimp, arctic copepod powder, sera micron, New Life Spectrum fry starter powder, finely crushed flake food COMMENTS & ADDITIONAL INFORMATION We couldn’t keep track of the number of times our Corys laid eggs, we collected, and they either failed to hatch, or failed to survive. The factors were manifold. We suspect there may only be one or two fertile males in the original breeding group. Many eggs were just not fertile. We also struggled with fighting off fungus spread in the hatching container. In the end, we were successful using two pieces of catappa leaf and a few alder cones that grow wild out on the edge of some swamps where we live. These release tannins, which help to fight off fungus spread. Also, the decomposition creates lots of context of microlife to flourish for baby corys to get their earliest source of food. Before we were really successful we tried a lot of things to trigger spawning: heavy water changes; using rainwater / ground water for water changes; cold water changes; feeding a wide variety of foods; over-feeding / cleaning after; altering lighting plans; leaving lights on at night; addition of live plants (crypts); addition of a small Hydor powerhead for flow . . . and then we had the afrementioned challenges of trying to hatch eggs and keep fry alive. Documented successes from folks in our fish club helped us, as we read some of their BAP submissions. It seems that if you’ve got a decent ratio of mature males and females, feed well, and keep their water quality up, they’ll do their thing eventually. We’ve had our adults for about a year before setting up their breeding tank, so, as with other catfish, they seem to take their time maturing to a breeding age. Once we had fry, we changed out the water regularly with R. O. Bottled water. But once we were about 2-3 weeks in, our corys spawned again. So we started another batch but just used tank water instead of R. O. water. That batch is going very strong - about 20-25 fry — plus, we found 5x fry from that batch in the parent tank that must have been attached to leaves somewhere. Some chemistry things we learned / are learning: (1) Raising fry in the little specimen containers is a stress on fish fry, and on fish breeders. Constant vigilance is needed to keep parameters from danger zones. Without filtration, ammonia and nitrite build up quickly. But with a sponge filter, nitrate builds up quickly as well. (2) Using catappa leaf litter and alder cones releases humic acid, and really makes pH dive. This keeps ammonia (NH3) buidup below the 7.0 pH threshold to ammonium (NH4+) which is _slightly_ less problematic for fish . . . but really not good in any way (3) R. O. Water, and our soft tap water, lacks buffer which prevents against pH crashes. We found that the pH crashed in the adult tank when we added some tetras, and kept finding them dead. We originally added a lot of catappa leaf litter and oak leaf litter along with alder cones to the parent tank. It was just too much, and as humic acid built up over time, the pH crashed — from 7.8 tap water to 6.0 (or lower . . . our kit really doesn’t measure pH lower than that). Science aside, the jury is in: Cory fry are the cutest fish fry in the world! We all love watching them wiggle around. I think this species is one we’ll continue breeding and raising up for a while. Our fish stores are always happy to have some to sell. But we will probably not hold them in the grow out context much beyond 3 weeks so that they can be added into the larger colony and grow up in a better environment.

I know this may not be too exciting but it was a shock to me when I got home from work first time they've tried to breed since I've had them and I got them safely moved to a container away from the mollies and platys.

We’ve been selling off Corydoras Aeneus (bronze corys) this past season out of this tank. They’re pretty good at hiding, so it’s hard to count them. Just dropped in a couple Omega One veggie rounds. Thought I’d share a short video. These are all home-raised.

Hi folks, Just asking out of curiosity more than anything. I have a breeding pair of bronze cory who are roughly 18 months old and 5 albino about 8 months old who have also started spawning for me. My question is will the albino get as big as the bronze as they are huge in comparison. All fish are nice and fat and healthy as I feed the tank well but the size difference is considerable. Like I said its not an issue just curiosity TIA

We are 3x weeks into raising up a small batch of Corydoras aeneus for BAP at our fish club. Just wanted to share this little video.

I recently had a Corydoras Paleatus offspring show up in my albino breeding tank. Are albino Corydoras an albino Paleatus? I always thought they were Aeneus.

This will be about the 8th time I've raised Cory cats. It's so rewarding and fun. These guys are about a month old now and then the fun begins. I'll drop them into a 10 gallon filled half way and as they grow I'll raise the water level gradually. Until then they get daily water changes. I find this part to be very exciting because once I put them into a larger body of water they seem to grow very fast after that.

Hello, we just recently bought four new bronze corydoras. One was very pale and had white circles around the eyes(white iris), this fish died in about 2 days. A few days after this another one of the corydoras started to lose color and the eyes also changed color (top picture, this was one of the darker ones from the bottom picture). She also swims a bit peculiar, with stomach facing the glass sometimes. She is swimming around in the top/middle area of the tank more often than staying at the bottom of the tank as one would expect. We also noticed that there was a bubble attatched to some feces. Now another one of the corydoras have had it's iris change color to this white outliner. we are quite concerned. They are eating well and shows no other physical signs of illness. Any suggestion as what we could do regarding this, I have not found any conclusive evidence as to what can be the cause of this can be on google. The three fishes are currently quarantined in a 13 gallon tank. Ammonia: 0 No3: 0 No2: 0 Ghd: >250 Khd: 6/107 PH: 6.8 I would very much appreciate some assistance, thanks in advance. /Felix