Albino Corydoras Dying....

[indigoj]

Hi,

I have a recently cycled 105l tank. Water stats all fine (0 ammonia, nitrite, nitrate less than 10, ph 7.2, low Kh 0f about 3) Other inhabitants are 6 Praecox Rainbows, 6 Tiger Barbs, 1 Featherfin Catfish and there were 5 corys, 3 albino and 2 bronze.

1 Albino Cory died about 4 days ago, wasn't too surprised as this particular fish was the 'loner' of the group. Then today, went out all day and came back to one dead albino cory. Again no marks, no bloating, no odd behaviour. The only similarlity is that I found both dead fish behind the filter.

The fish have sand substrate, plenty of wood, plants and rocks to hide in. The filter is a Fluval 3+. I use an airstone. I do 50% water change at least twice weekly because it is a new tank. Fish are fed a combination of flake, catfish pellets and algae wafers which seems to satisfy all hungry mouths. They get frozen or live food at least twice a week this is usually bloodworm as I keep this to feed my spiney eels anyway. (different tank)

There are no meds or salt in the tank, apart from dechlorinator. Since this second death I have turned the flow on the filter down a little in case they were having trouble with the fairly strong current.

Any ideas or were these fish just not strong enough?

Thanks

 

[scooterchick]

How recently cycled? How long were the fish in there and were they there when you were cycling the tank? It could be they just weren't strong enough to survive the cycling process.

By my reckoning you're bordering on being overstocked, that's quite a lot of fish in quite a small tank. Couple that with being recently cycled = stressed fish. You're doing the right thing with frequent water changes although perhaps you could do 25% x 4 times a week. I think with the amount of fish you have you will need to do regular changes even when the tank is fully mature. How are the tigers? Are they showing any signs of aggression?

Sorry about your corys, such cute wee fish.

 

[indigoj]

The featherfin is only a baby (and is the biggest fish by far in the tank) and will be moved to my bigger tank when it has cycled.

I cycled this tank without fish. The barbs has been a bit nippy with each other but not the other fish. All fish at present are juveniles.

 

[scooterchick]

Sounds as though maybe the poor wee fishes maybe just weren't strong enough. Just keep an eye on the rest, hope you have no further problems. x

 

[indigoj]

Thanks. Fingers crossed!

 

[jollysue]

Your Corydorus are a river fish and the filter flow should not hurt them. Most albinos are from a strong species (C. aeneus, C. palateus, C. sterbai) who are able to take a lot. You don't mention if there are temp changes. Corys generally like a cool water change after which the water warms up from the heater. This is the natural process from the river floods for them. It actually helps to induce spawning in adults. But sudden warm temp changes or some extreme change that does not return to what they are normally acclimated to, could cause additional stress. Another problem might be poor oxygenation. As a river fish they like lots of aeration. Have they been darting to the surface to gulp air a lot?

Other problems might be changes in ph or hardness. One big stressor for fish is change that is big and does not return to their normal range in almost any area. Most can take a sudden change that then returns to normal, but a big change that does not return takes a long time to acclimate to and should be done slowly--days /weeks /months. For instance, even changing bad conditions in a tank too fast can kill fish that have acclimated to it.

Any time a fish that is a shoaling fish goes off by himself and separates from his group it is troublesome. The fish should be hospitalized.