All My Beloved Fish Are Dying!

[grumpymole]

hi guys, all of my fish are huddled up in a corner of my tank and keep dying, so far the following have died:
2 neon tetra, 2 mollies, 4 guppys, 1 black phantom tetra, 1 cory catfish, 1 haalequin.
what do i do?!!!
my tank is 80g- and i now have 6 neon tetra, 1 guppy, 3 black phantom tetra, 1 cory catfish, 3 harlequins, 4 blood fin tetra, 1 wheather loach, 7 marble hatchets, 4 golden pencils and 5 x-ray tetra
WHAT DO I DO!!???!!???
please help fast, they are dying by the second.

 

[black angel]

Need more info

How long has the tank been set up, filtration and how do you clean it?
Water changes, how much and do you temperature match and add dechlorinator.

What readings do you have for ammonia, nitrite, nitrate and ph.

Any new arrivals and is there anything visible on the fish?

 

[grumpymole]

set up for 1 year, bio life filter, clean with a clean wet cloth 20% water change every 2 weeks- temp is 79, dont add dechlorinator as i dont know what it is ph 6.6- new arrivals is a wheather loache which arrived last week, nothing visible on fish apart from scale.

 

[rdd1952]

Dechlorinator is a water conditioner such as Stress Coat to remove chlorine and chloramine. If you are on a municipal water supply it is VERY important as the chlorine will kill off your bacteria colony (and your fish eventually). Since you've had the tank running for a year though, I doubt that is the problem.

Have you tested your ammonia and nitrite readings? That could be the problem. Also, you said the weather loach was the only new arrival, have you used any new chemicals (fertilizers, pH adjusters, algae killers, etc) or added any new decorations, plants, etc to the tank? Obviously, there is something amiss in the tank that isn't visible to the eye.

 

[black angel]

I dont know much about the bio life but i dont know if its big enough for a reasonable turnover for the size of your tank.
You relly should add a dechlorinator as this will get rid of anything harmful chemical wise in the water.
Invest in some test kits as well as you may have toxic water.
All new fish must be quarantined before you add them as they are more than likely carrying a disease that could infect your fish.
Change some of your water weekly rather then twice weekly of around 40% but just now i think you should do 30% every 3 days until you get your water tested to see whats going on. Use a gravel vac as well.
How often are you cleaning the filter and how? If it has any sponge in it then that must be rinsed in old tank water.
I think as well you may need to get another internal or external filter. Hopefully someone can tell you whether the bio life is adequate for the amount of fish you have.

 

[grumpymole]

bio life is quite big, i dont know about ammonia or mitrate, so will get test kit and de clorinater round about............
.........
........
now, im getting into the car...
be back in half an hour.....

 

[dwarfgourami]

Dechlorinator is a water conditioner such as Stress Coat to remove chlorine and chloramine. If you are on a municipal water supply it is VERY important as the chlorine will kill off your bacteria colony (and your fish eventually). Since you've had the tank running for a year though, I doubt that is the problem.

Could it be that the water board have changed what they add to the water? That would explain that they are all dying so suddenly. Just a thought.

 

[bunjiweb]

have you checked your levels - nitrite, nitrate & ammonia?

Ben