Endler Deaths!

[Bruce1]

Hi All,
Can any one offer reason why this happened.
Had a 48" tank with aprox 36 Endlers in together with a breeding trap containing about 20 fry. Have had a problem with snails recently and over the weekend decided that the only way to get rid of the problem was to totally clean the tank (snails were all over the place even in the filter!).
Removed some of the tanks water and put into a spare 24" tank and waited until it was the same temp. as the main tanks (75F)
and added a small filteration unit and airstone. The adults and fry were put into the tank on sunday evening, in readiness for an early start monday. By 7am had lost two females and by 7pm only had four females remaining, as a generalization the males died first! The fry however at this stage were not affected and last evening were released fronm the trap into the 24" tank. However, by this morning there were none of these left either.
The only reason I can think of is some form of stress, but as far as I was aware I carried out the relocation as quickly and carefully as possible.

Has any one any ideas.

Thanks,
Bruce

 

[moll]

Was the tank you moved them to cycled? or was it a brand new filter.
If it was a new filter then the ammonia freom 36 fish could build up quickly in a small tank.

 

[lilfishie]

^^ i agree, you moved some water over but its ot the water that contains the bacteria, its mainly in the gravel and filter

 

[Duck and Dive]

You should'nt have added that many at first. You should have added a few then waited a week or two cheacking on the water quality. Then added the rest.

 

[OldMan47]

Time to look closer at that tank. 50 endlers is not much bioload when half are fry and should not have been able to ruin even an uncycled tank's water in 12 hours. I would not hesitate to put that many in an uncycled 20 but would do frequent water changes and expect no deaths. There is something else going on there. Had the tank been in a storage situation where something could have gotten in it? Where did the filter come from? Any previous issues related to the filter or the tank? I am stunned by how fast things went bad.

 

[Bruce1]

The filter was new, but the sponge was soaked in the original tank for an hour and then some of "gunge" from that tanks filter squeezed onto it! as it was not possible to put the old filter in the new tank. I had presumed/hoped that would have been fine for that short period of time.
Maybe looking back could have added the fish in several lots, but when the infestation of snails increases by the minute drastic action was needed.
Regarding the water in the new tanks water, I have kept the set up running and noticed yesterday evening that there is a distict cloudy look to the water and looking in the filter there is a reddish-brown deposit on the sponge, does this give any where near a deffinitive answer?
It was the pace of the incident that also stunned me as it hardly gave time to weigh up the options!
As far as I am aware there were no storage issues with the tank, but will give it a through clean before reusing it.
Just to let you know that two females have survived and are back in the original tank, together with 3 corydoras (who were for the whole episode were kept in a jam jar on the boiler in the kichen!) and are looking fine.

 

[OldMan47]

You also mentioned snails. Depending on how many snails and how large they can be a very significant bioload. I'm not sure what else to suggest.