25% tank wipe out Help

  1. can haz catfishies? Member Member

    ok i will keep this short, last night i had to move all my fish from my 300 to a spare 200 as my 300 was leaking, i transfered over 200litres of water from the 1st tank and the filter and heater, i then caught and moved all the fish from the 300 to the 200 so i could repair the 300, i left them there over night checked this morning everything was fine before i went to work, got home 7 hours later and i found quite a few dead or dying,
    a couple of the dying fish are swiming upside down or swiming very weakly, while watching them a few seem to be gasping
    in the mix of what i have lost is: glowlight tetras, neon tetras, congo tetras a betta, and i am loosing a flying fox.
    in among them the fish that look healthy and are swimming around normally are
    some glowlight tetras, neon tetras, a rummy nose tetra a opaline gourami, a bn plec, ottos and cory's.
    i have tested the water and the readings are
    ammonia 0
    nitrite 0
    nitrate 10-15 ppm
    ph 8.0
    temp is stable at 25*C
    of the dead fish none have any obvious signs of illness, no bloating no popping eyes no white spots and no red gills
    i have done a 50% wc and just hope thats enough to save the rest
  2. RogueAgent94 Fishlore Legend Member

    Sorry about you loosing so many fish! Did the temperature change at all? It could be that you had a minor ammonia swing when you moved the fish over. I'm thinking this because the 300liter tank spread out the waste more than the 200liter tank does. So that gave the bacteria in the filter more time to remove it. But when the fish were confined to a smaller tank then the waste levels went up before the bacteria could cover the extra ammonia a nitrite. That small spike could have killed a few fish which released more ammonia which could have affected other fish. This is all theory though. I'm not sure if it works that way but I assume it would.

  3. can haz catfishies? Member Member

    well i have just been to my lfs and had them test my water to make sure i was getting true readings from my test kit, he came up with identical results to me apart from a slight reading of nitrite,
    the only two other things i can think of is either shock, cause i had to move them quickly as the tank was leaking alot,
    or if somehow i have managed to get silicone on my hands then into the 200 litre tank
  4. wisecrackerz Well Known Member Member

    did you have airation in the larger tank, and do you have airation in the smaller tank? that sounds a little like really far gone O2 starvation, but in that much time, and looking at the species of fish you've lost vs didn't lose... doesn't seem very likely AT ALL. hm. is it possible that there was some kind of residue in the 200L, before you put the water in it?

  5. can haz catfishies? Member Member

    wise thats what i am thinking it has to be something like that as other than the smaller size of the tank nothing changed, same water, same temp, same filter no undue readings on the tests, it just threw me that it was a few of each type rather than all of them and all different sizes of fish too, the one that has upset my the most is dave the betta, he was such an awesome little dude

    and rogue i did think low o2 but my betta dave should have survived that with being able to take in air from the surface
  6. RogueAgent94 Fishlore Legend Member

    Yeah low O2 would result in all the fish being sickish. Also your correct, a betta is a labyrinth fish so he would have been the last to die from low O2 in the water.
  7. jerilovesfrogs Fishlore VIP Member

    I personally don't think low o2 would be the reason....just because I have a tank with no aeration, no filter....and they are fine. I add fresh water though...every couple weeks though...which brings o2 in. if fish are wiped out, it could be columnaris...which can be hard to see...the fish just die.

    not saying it couldn't be lack of o2, just seems unlikely, to me


  8. MD Angels Well Known Member Member

    I was thinking the same thing as wise about there being a residue in the stored tank. Even if one day while it was stored there was something being sprayed nearby (aerosols are DEADLY).

    Sorry about your tank leaking! :( I hope the rest will be ok.
  9. can haz catfishies? Member Member

    well i am up to about 50% loss at the moment,
    the remaining fish mostly seem ok but i am keeping a close eye on them for now i did have a very close look for signs of columnaris and i can see nothing at all to indicate it and it wiped out so many so quickly, we are talking a 6hr period from healthy to dead in alot of them
  10. jerilovesfrogs Fishlore VIP Member

    thats what it does....fish seem healthy one minute, the next,dead. I hope you dont lose them all...


  11. can haz catfishies? Member Member

    I am really hoping it was a nitrite spike due to moving everything to a smaller tank with no substrate so less good bacteria for the night, I have lost so many but out of the ones left only one is looking a little unhealthy now, I am going to start moving them back into the 300 shortly as it is now sealed and replanted and just hope for the best
  12. toosie Well Known Member Member

    Give your silicone AT LEAST 24 hours to cure before using it for the fish. If it hasn't been that long, I'd drain it and leave it longer, then rinse it really well before refilling for fish use.
  13. can haz catfishies? Member Member

    I did give it 24hrs and filled drained filled again, the fish are now back in the 300 I have lost about 25 fish in all, and a few still don't look great but a few of them seem to be perking up slightly I will just have to hope that they survive now.
  14. toosie Well Known Member Member

    Well, best of luck to you and your fishies. Hope the rest have a speedy recovery.
  15. can haz catfishies? Member Member

    just an update, i transfered the last fish back over last night and this morning i have no more losses and the fish that looked weak and lethargic seem to be back to almost normal again, i dont know what caused all of this but atleast i have some survivors