Disappearing Fish

[Bertie]

I have a 240litre aquarium which has been up and running for approximately one year now. I currently house 2 small Clown Loaches (yes, I know they will grow); a pair of Kribs; 4 Corys; 2 Giant Danios and 2 Zebra Danios.The first 11 months went smoothly but now I am fearful of adding fish as the tank has become slightly strange....
It all started when I added 4 Black Widow tetras to the mix - they lasted about 2 hours before being devoured. Since then I have added 4 platies (one remains) and I'm scared to add any more fish.
I have a pair of Opaline Gouramis (well, not a pair any more as the female died/was killed last night) and believe that the male could be responsible for this. He was added a few months ago.
Can anyone shed any light on why the tank has become so aggressive and if you believe that the Gourami or Clown Loaches are to blame?

 

[jayjay]

i doubt it was either of the fish you mentioned, have you done any water tests? that could well be the problem.... clown loaches hardly ever kill fish until they reach over 10 inches and they start breeding i believe.

 

[Leslie]

The Gourami could indeed be the problem.

 

[Bertie]

i doubt it was either of the fish you mentioned, have you done any water tests? that could well be the problem.... clown loaches hardly ever kill fish until they reach over 10 inches and they start breeding i believe.

Could water conditions affect the nature of fish? It all started to go crazy with the introduction of the Black Widow Tetras.

 

[jayjay]

i'm not sure if the conditions affects behaviour i know it wouldn't make them happy.

you say you have a pair of kribs are they breeding? may be the problem if they are.

2 small Clown Loaches, a pair of Kribs, 4 Corys, 2 Giant Danios and 2 Zebra Danios, is that what you have because you start adding to it?

 

[Bertie]

i'm not sure if the conditions affects behaviour i know it wouldn't make them happy.

you say you have a pair of kribs are they breeding? may be the problem if they are.

2 small Clown Loaches, a pair of Kribs, 4 Corys, 2 Giant Danios and 2 Zebra Danios, is that what you have because you start adding to it?

That is what I have at present and was just hoping to add some Neons or Harlequins (something to add colour/movement). I'm scared to put anything in there now.

 

[jayjay]

you said you had a platy and an opaline gourami??

do you know if the kribs are a breeding pair?

if i was you i wouldn't have the giant danio's i'd take them to an lfs and get say 4 more zebra danio's.

what are you going to do with the clowns when they get older and bigger?

and do you know kribs doing really like anything that occupies the lower levels of the tank like cories i don't think.