My Rio Negro Corydoras Tank

[Korsaaven]

Hi,

Im new to this forum and would like to share my Corydoras tank. I believe I have 12 Corydoras duplicareus and 2 Corydoras sp. 121 (both females) in my colony. If you see any adolfoi or imitator in my colony please let me know.







They are kept in a 29 gallon tank in water that's liquid rock (~kH=16, pH 7.0-7.5). There's is strong water flow in the tank since I'm using two Penguin filters (one rated for 55 gallons and one rated for 30 gallons). They are kept at 78F.

Despite my liquid rock water my colony has spawned four times in the past 40 days. Feeding them live blackworms probably triggered them to spawn. The fry would hatch in this water but would not survive. For the third spawn I transferred the eggs into RO water with a pH ~5-6 and was able to get surviving fry ( they are now 6-7 days old). I have a 4th batch of eggs and are now in a separate container with RO water.



My two C121s arent interested in participating in the spawning and doesnt interact with any duplicareus males. They may swim with them as a group but never have seen them "dance" with the duplicareus males.

[Korsaaven]

I was on vacation for 9 days and left week-day old and 2 week-old duplicareus fry in a marineland bio-wheel 5-gallon hex and subjected them to do a once a day pinch of hikari first bites feeding regimen. Well not exactly just hikari first bites i also added 1/4th portion of a Hikari Sinking Wafer every 3 days (but i think this was feasted on by the snails). I asked my uncle to do the feeding (I prepared small plastic pouches of food for him to dump into the aquarium). Since he wasn't adept in aquarium maintenance I didnt ask him to do any water changes. Because there wasnt going to be daily water changes for 9 days, I had to limit the feeding to a pinch of hikari first bites once a day in order to avoid ammonia build-up. The water I was using in the tank is RO water with a KH of 3 and pH range of 5-6. No tap water was mixed with the RO water. Somehow the fry thrived on this diet and in this water when i was away. I took this pictures today (one day after i arrived from vacation) before doing a water change:







The tank was assembled 2 days before I had to go on vacation (the vacation was planned months ahead, the Corydoras spawning wasnt expected =p). I took the sand from my main Corydoras tank. As you could see in the last pic you can see blackworms sticking out of the sand. These were blackworms that avoided the adult corydoras and hitch-hiked when i transferred the gravel to the 5 gallon hex. Originally this tank had gravel as substrate but i removed all of them and replaced it with sand. The plants you see were the plants that existed in the tank when it had gravel in it. I also placed assassin snails in the tank as scavengers and burrowers.I placed ceramic rings from my my other tanks in order to improve biofiltration eventhough i had a cycled biowheel in the tank. I also added an airstone driven by a 10 gallon-rated air pump to provide more water circulation. Looks like the extra filtration helped because prior to my vacation I was suffering ammonia spikes but now i checked my tank parameters ammonia is 0, nitrites is 0. In retrospect I probably can attribute this ammonia spikes i was observing to overfeeding.

despite the limitations the fry were subjected to during my 9 day vacation, they survived and are steadily developing.

[bigbird]

very nice and congrats. cheers jk

[christiansen]

nice job with the fry ! keep posting u're progress!