Who is the aggressor? :(

[Gog77]

I have had a problem for the last month. At first I thought it must have been my tank but yesterday confirmed that there is a very aggressive fish in the tank. The problem is I can't work out which one.

OK the problem I have been having is keeping Bristle Nosed Catfish which is usually pretty easy. I have now lost my 4th in the last month. I had a failry large one which lived for over 6 years die so I bought a replacement. 2 days later I found it dead after showing no signs of illness so went and bought another and it happened again and once again after that. I thought it was my tank which may cause the problem even though these little guys are as tough as old boots. So I left it for about 2 - 3 weeks and got another on Saturday.

Sunday I wake up and the little guy is fine. Cleaning up the algae in the tank vigorously. I go and have breakfast after that I went to feed them and find it dead! It had bites taken out of his head and his tail. I also bought 4 Glowlights which disappeared overnight

I can't work out which fish it is? This is what I have in my tank right now.

* 2 Clown Loaches.
1 is approx. 12 CM long and seems pretty placid the other is about 7 CM and seems to be a little aggressive at times.

* 1 Silver Shark
It is about 15 - 16 cm long and looks to be the most peaceful fish in the tank.

* 4 Black Widow Tetras.
Quite large for a Black Widow. About 4 - 5 CM in length. I've never noticed to much aggression but chased the Glowlight Tetra's around when they arrived

I am considering buying a very large Bristlenose to try and stop this but they are very rare around here and are quite expensive! I usually can only find them around here at 2 - 3 cm long.

Any help would be appreciated here.

Thanks in advance![/list]

 

[sir_dudeguy]

by silver shark, do you mean bala sharks? i dont know of any shark called a silver shark (might be tho...dont really pay attention to them much) but i know that bala's are silver...if its a bala, it wouldnt be him doing it. I would never think of a clown loach of doing that, but you say the one is more aggressive at times so maybe him...any snales? i've had those kill fish before. and i dont think a tetra could eat a fish if it tried...or kill one for that matter

 

[Lonewolfblue]

If it's the catfish that looks like a silver shark, could possibly be that. They can be a little aggressive.

 

[Gog77]

It's a Bala Shark. There called Silver Sharks here all the time. Here is a pic of him:

BTW no Snails in the tank.

 

[DeFeKt]

at a glance i would say the tetras,
balas and the loaches are more scavengers, i would find it hard to believe they would single out a fish.

btw your bala seems to have a cloudy eye

Matt.

 

[Gog77]

at a glance i would say the tetras,
balas and the loaches are more scavengers, i would find it hard to believe they would single out a fish.

btw your bala seems to have a cloudy eye

I'm thinking the Tetra's as well.

The Bala is fine. I thought the same thing when I uploaded the pic but his eyes are clear. Must have been the flash.

 

[tropicfishman]

well lets consider the obvious here, first are you adding any salt to the tan k for any reason? plecos hate salt, they can't tolerate it at all? and whast your water parameters, mainly Ammonia, PH, nitrates, nitrites

 

[Gog77]

well lets consider the obvious here, first are you adding any salt to the tan k for any reason? plecos hate salt, they can't tolerate it at all? and whast your water parameters, mainly Ammonia, PH, nitrates, nitrites

No salts are in the tank. Unless aquarium conditioner has salt in it? I don't have my tester kit here right now, my friend has it but last time I checked (Friday Night) everything seemed normal.

 

[Gog77]

Just got my kit back and the nitrate level was fairly high.

PH 7.2 - 7.4
High PH 7.4
Ammonia 0
Nitrite 0
Nitrate 80

:?

 

[jcarlilesiu]

i don't think an 80 would make a bala aggressive... i read some where that tropical fish can tolerate VERY high levels of nitrate, though uncomfortable. I would look for another culprit, of all the fish in my tank that are larger, the clown loach and balas are the most peaceful, even with white clouds, and tetras