Unexplained Fish Death

[PJ5142]

Hi All,

I've joined the Forum as i'm having some unexplained deaths in my tropical tank.

I've had the tank setup for over 3 months now. The tank is around 62 litres with a bowed front and set up on a timer for the lights. I've no algae growing and have a mix of plants and ornaments for the fish to swim in. I had the tank setup with 3 Angel fish, 5 mickey mouse platys and 3 small catfish (not sure of the exact type). All the fish were happy and the water tested perfect when i took it into a local shop so i decided to buy some more fish. I got 4 tetras (look similar to black widow tetras - cant remember the exact name) and 1 black shark with a red tail. I think this would have brought the tank to capacity but all fish are/were very small when in the tank together.

Since then my fish have started to die at random. Two of the platy's have died and one looks like it's about to go, the shark has died and all 3 catfish have gone. The fish themselves all looked healthy (no spots, rotting fins or worms), they dont fight or attack each other, i've taken the water in to be tested and there's no ammonia, chlorine or nitrate build up and the temperatures holding steady at around 25 degrees C. The 'ill' platy is just resting at the bottow of the tank behind a plant and the rear fin has contracted (it's normally a triangular shape). It's still eating as normal and swims if another fish gets close. The fish that died showed similar behaviour. I thought it might be overcrowding but all the fish are very small at present. Whatever it is it seems to be 'infecting' more fish.

I'd appreciate any help here as i'm new to tropical fish keeping and my local shop can't think of any reason why their dying.

 

[anon02]

Did you do a "fish in" or a "fishless" cycle ?

 

[PJ5142]

Did you do a "fish in" or a "fishless" cycle ?

I ran the tank for just over 3 weeks without any fish when i first set it up. I used stress zyme to kick start the nitrate process and after the 3 week period the water tested clear for nitrates/ammonia and chlorine.

Is there any kind of broad spectrum medication i could try in case this is a disease of some sort?

 

[onebto]

Quite a controversial subject but in my humble opinion that stress zyme stuff really did not do much from the point of view of cycling your tank, so your tank was not cycled properly and a sign that your tank is cycled is having Nitrates its 0 ammonia and Nitrite that you are looking for. I recommend you have a look at the beginners resource centre in this forum and read the nitrogen cycle and the fish in cycle it will help you and is basic information that every fish owner should know.

Secondly I would recommend you get your own water testing kit as a lot of LFS are a little unreliable especially if they use the test strips which are very close to useless. A lot of people here use the API fresh water master test kit you can get them in a lot of LFS on line including ebay, Salifert are a good make to.

So find out what your water stats are : Ammonia, Nitrite, Nitrate and PH .

Lots of water changes will do a lot of good and never any harm just remember to make sure the water temperature does not lower to much as this will put your fish under more stress I take it you use a dechlorinate to treat the water?

Regards onebto

 

[PJ5142]

Quite a controversial subject but in my humble opinion that stress zyme stuff really did not do much from the point of view of cycling your tank, so your tank was not cycled properly and a sign that your tank is cycled is having Nitrates its 0 ammonia and Nitrite that you are looking for. I recommend you have a look at the beginners resource centre in this forum and read the nitrogen cycle and the fish in cycle it will help you and is basic information that every fish owner should know.

Secondly I would recommend you get your own water testing kit as a lot of LFS are a little unreliable especially if they use the test strips which are very close to useless. A lot of people here use the API fresh water master test kit you can get them in a lot of LFS on line including ebay, Salifert are a good make to.

So find out what your water stats are : Ammonia, Nitrite, Nitrate and PH .

Lots of water changes will do a lot of good and never any harm just remember to make sure the water temperature does not lower to much as this will put your fish under more stress I take it you use a dechlorinate to treat the water?

Regards onebto

I purchased an API freshwater test kit and got the following results:

7.2 - 7.4pH
0ppm Ammonia
0ppm Nitrite
30 - 40ppm Nitrate

Temperature holds at a steady 25 degrees C.

The fish seem to of stopped dieing now, i've 3 angel fish, 2 platys and the 4 tetras left. All seem ok but i'd like to know why the others died??

 

[onebto]

Well the good news is that the fish have stopped dying, you have your own test kit which is priceless in this hobby and your water stats sound good I would not want my Nitrates to go any higher but thats me its always worth while checking your source water supply to see what levels they have I have heard people that have done endless water changes to drop there nitrates to eventually discover the water out of the sink is the cause.


As to why your fish died it may remain a mystery there possibility your tank was never properly cycled but now the bacteria has taken hold, it could of been an infection or just plain stress the evidence is almost likely to have gone by now well lets hope so. if you ever have a problem again there is a post at the top of the tropical fish emergencies which recommends the exact details required for those on here good at diagnosing to give you the best advice and though morbid pictures help no end.

I hope all is sorted and you can continue to enjoy your tank regards onebto