My loaches and other fish dying suddenly (with tank pics)

[Symbiosis]

Hey guys,

My 5x2x2 is stocked with silver sharks, flagtail, schools of loaches and plecos. they have been inhabitant of the tank for the past 3 years with no problem (it is a quite overstocked tank). For some reason i came home today and saw one of my larger silver sharks dead on the bottom along with one of my small clown loach ~8cm and another 12cm both dead. I tested the water out and it had no ammonia, no nitrite but the nitrate level was little on the high side as i have been slack with the water change lately.... i had a closer look at the loaches and a couple of them seems to have the cloudy eye look to them so i was wondering whether it was ich that has caused this. only other thing i can think of is prob as we have been getting slightly colder winters this year my temp of the tank was kept at 25 degrees.... anyway so i did a 50% water change but later today when i got home again and now i noticed one of my common pleco is now dead on the bottom.... can anyone think of any other reasons taht it would caused that?


Any help appreciated cheers

Eric

 

[oscar n redtail cat]

mabey it might be a fish killing them u never no or keep water changeing and add salt
good luck.

 

[Cammo X]

In my experience the cloudy eye is caused by ammonia or bacteria in the water? could be other fish killing them?

Cammo X

 

[Symbiosis]

What fish would kill them? they have all been in the same tank for almost 3 years now.... so what should i do about it? just keep doing water changes and add salt?? btw how much salt should i add?

 

[Cammo X]

1 teaspoon per 20l im pretty sure, other people have different methods for adding salt, but i generally go by that rule for the fiosh you have.

Cammo X

 

[Symbiosis]

thanx for the tip cammo... if it was a bacterial problem, what would cause it??

cheers

Eric

 

[cassharper]

I really wouldn't add salt to loaches....

http://www.fishyfarmacy.com/fish_diseases/eyes.html

Great site, works even better than blind guessing

 

[beantickler]

What was the nitrate level? How many weeks did you slack? 50% was WAY too much if the nitrates were that high... That will shock a fish going from dirty 100ppm down to 50ppm in a matter of minutes... Killing a common plec is no easy task...lol

 

[Arachnar]

Sometimes that stable tank can be the exact problem. In nature the environment is dynamic in the aquarium it is often more static. When you have a tank, and keep the water temp constant, water chemistry, suddenly a bacteria that fits right in suddenly has all the right conditions to thrive and out competes other organisms. It becomes pathogenic and starts attacking fish, that's what happened with mycobacterium for me where it thrived in the high temps and killed quite a few fish.

I can't recommend salt as I haven't tried it but check out the site cassharper showed you.
The site below is also very good.
Double click on health and diseases

 

[importracer]

If there are no apparent wounds on the fish, then chances are you do not have any killer fish.....Try remembering what you did earlier this week.... Before their deaths, you possibly were doing some house cleaning and some of the chemicals blew into the tank.....