Help, baby Sterbai dying

[sammy]

My husband and I have been doing the fish thing for about 2-3 years now. We have a 1000 litre tank with a variety of fish among which we have 1 ancistrus, 1 chaestoma, 2 panaque maccus, 2 panda cory, 8 pepper cory and 8 sterbai cory. I love the corydora.

Lately our sterbai have started spawning alot so we moved them to their own tank where they spawn every 2 - 4 weeks. My problem now is getting the fry to survive past 6 weeks. Does anybody have any tips as they are dying daily in batches and its breaking my heart to lose the little guys. Once the eggs hatch ive been keeping them in a 2 litre ice cream dish feeding them liquifry until they about 2-3 weeks old. Tried BBS but they didnt take to it - tried microworm not sure if they taking to that either - after 3 weeks i transfer them to a separate tank and feed them crushed tetra bits and spirulina flake mix. They do fine until they get to 6 weeks plus then they just start dying - all the small ones from subsequent hatchings that are put into that tank survive while the older ones r dying so surely it cant be the water or they would all die?

Any input would be appreciated.

Sorry to do a heavy post on my first time - but desparate times call for desparate measures.

Thanks

Sammy

 

[Lornek8]

Sorry for your losses.
So at 3 weeks the fry are added to the tank, survive to 6 weeks then perish? But any subsequent fry survive until 6 weeks? So you might have fry of age 3 weeks, 4 weeks, 5 week all in the tank and nothing perishes until they reach the 6 week mark?

Are there any markings on the perished fry? One of the things I was thinking was a bacterial infection of sorts. One of the common reasons for fry death amongst bottom dwellers is a build-up of a biofilm on the bottom of the tank. Is there substrate or is it a bare bottom tank? How often do you clean the tank? Do you scrub the bottom if its bare botttom? Do you gravel vac? It seems strange that the younger fry don't perish as they should be the more delicate ones. Thinking some sort of infection that takes some time to develop which is why they survive to 6 weeks.

 

[bigbird]

ok, agree with Lornek. I have breed sterbai and leopardis.
I do need to ask you some more questions though.
So if I understand this correct, you have 1 large 1000l tank and another tank where you put the corys in for breeding . Any more tanks ? At 6weeks- do you place the fry back into the large tank ? How often do you do water changes and how much ? What is your substrate ? Do you have any decor in the tank ? Do you leave the parents in this tank with the fry ? cheers jk :thumbup:

 

[sammy]

Hi

Thanks for the replies. Ok so I have the sterbai adults in a 60 litre tank - when the fry are about three weeks I transferred them from the ice cream dish to a separate 40 litre tank I set up for them. It has a sponge filter and java moss - I recently added gravel as i read that could help reduce bacterial issues. I did not cover the whole floor of the tank tho and I did notice a white film on the tank bottom that was exposed. I started scraping that off. I would do water changes twice daily and vacuum each time. I didn't use a gravel vacuum tho as the gravel was not very thick so i would just suck up the left over food off the gravel. The dead fry have no markings except that some would be very furry. These fry would not have been dead long e.g. they were alive for the morning water change and dead when I got home from work and furry but not all the corpses were furry. I was using aged water for the water changes.

The thing that gets me is as Lornek8 says - I have various aged fry in the tank so why do all the old ones die. If the water parameters are drastically off surely the smallest fry would be susceptible first unless its a long term infection. Out of desperation I de-comissioned the baby tank now and put whats left of the fry into the adult sterbai tank with lots of Java moss. Ive lost about 40 out of 60 fry that had reached about 6 weeks. BUT I have another 60 odd newly hatched fry (4 days old) so I want to correct any issues before I set up the tank again and try and avoid the same loss ratio.

Ive read on various posts that a large loss ratio for sterbai fry is fairly common (this is alarming). Im an eternal optimist _ i cant accept that _ there must be a way to stop these cute little guys from dying.

Any suggestions would be welcome.

 

[Lornek8]

What are you feeding the fry?

Edit: nevermind you already said.

 

[Gem400]

Have you tried placing some of the juveniles back in with the parents to see how they get on? Juveniles should be ok to put back in at 1cm if you give them some cover. My cory fry take frozen bbs quite readily, liquify is also quite useful for cory fry and crushed tabimin or fine fry food for the older ones.

It is very strange to lose them at that age, have you considered adding something to the fry tank that has natural anti-fungal properties like almond leaves etc?

 

[MICKSNOWDOG]

it was reccomended to me by a successful breeder to keep anything under 3cm under 23degrees

 

[Irene0100]

hard to tell without seeing the set up. water qual has to be high on the list - I know you are doing lots of water changes but what water do you use?
could be fungal infection or need more diet variety at that age. I would give tank a good clean then treat with small does of pimafix, also add some crushed flake to the diet and zm100.
have you tried adding plants as these are good at absorbing toxins from the water?
what temp do you keep then at? as they get larger they need higher disolved oxygen.

 

[aew]

what temp do you have in your tank?
Agreed with Micksnowdog. The temp need to be on the lower side.
Also, shallow tank is better than deep tank.