Help! 6 Deaths Over Night

[fishyfreda]

I have a well established tropical tank, running for about 18 months with no dramas as yet, i have a selection of fish in my 200litre tank.....many varieties of barbs, rainbows, mollies and platys...

i did my regular water change last night, 20% and as far as i am aware did nothing out of the ordinary but have had 6 barb deaths overnight

did some water testing and nitrites slightly higher than normal, around .25 i think, no higher.

Do i need to do an immediate water change again ?

The other fish have been all close to the top of the tank today so i have turned on air stone pump and this has seen them distribute a bit more. think thats all info i can think of....anyone there to help me ?

thanks !!!

 

[The young one]

Did you dechlorinate the water?

 

[fishyfreda]

Did you dechlorinate the water?

yes dechlor as usual didnt wash filter this time......

 

[Gilli]

I'd do a 50% water change & increase the airation of the tank as much as you can. You need to do daily water changes until your nitrites hit 0. It seems to imply that your filter isnt coping - check to see if its flowing correctly.

Did you put roughly the same temperature of new water in? Have you changed your feeds at all? did you dechlorinate correctly? Have you used any sprays in the room? Added any new fish? Just trying to get some clues....

 

[fishyfreda]

I'd do a 50% water change & increase the airation of the tank as much as you can. You need to do daily water changes until your nitrites hit 0. It seems to imply that your filter isnt coping - check to see if its flowing correctly.

Did you put roughly the same temperature of new water in? Have you changed your feeds at all? did you dechlorinate correctly? Have you used any sprays in the room? Added any new fish? Just trying to get some clues....

hi thanks for replying
yes, i did de-chlorinate
no new fish
no sprays
same-ish temp water back in
same feeding

really scratching my head on this one, will do water changes and keep up aeration, off to check filter but to be really honest not sure what i am looking for ?!?!?!?

thanks again..