sudden death of all my fish

[ras2883]

Hi,
I am a new member here.
I recently lost all my marine fish in one night and looking for some help in analysing the cause.
I have a 10 gallon tank with 2-3 inch of substrate and 7-8 lbs live rock.
Have some algae issues.
Have some macro algae.
Had 5 dwarf sea horses and mandarin goby.
Used to feed them fresh hatched brine shrimp.

Had all of them closed to 2-3 weeks (goby more than a month).
yesterday night they all suddenly died.

I tested the water,
Ph - 8 - 8.2,
NH3 - 0.25,
NO2 - 5ppm
NO3 - 5.

There was a sudden spike in nitrate (previous night it was zero), but I do not know if this was the cause of the effect of the dead fish.
The snails and even some grown shrimp are doing well.

have changed 20% water, will do more next 2 days.


Can the experienced Folk please help in what could have caused this or to prevent it in the future.

Regards.

 

[xfactor1315]

Something died and caused spike in nh3 and killed the rest most likely.

 

[ras2883]

Hi xfactor1315,
Thank you for your reply.
The ammonia level was the same as before, it was nitrate which had increased.
But I agree that it might have been the death of a fish which could have caused the spike of the nitrate and killed the fish.
To prevent this in the future I am thinking of using a bag of nitrates and NH3 absorbing media and activated charcoal, which would absorb any spikes. Do you think this would work? How about adding some "Seachem Purigen 250ml" to the mix of activated charcoal.

 

[gone fishin]

Do you mean the ammonia has been .25 for a while. If so this is most likely what them off. A 10 gallon can be very hard to keep. With such a small water volume things can go south very fast and it doesn't take much. I believe you said you was experiencing algae problems. I would suspect excess nutrients from possible overfeeding.

 

[xfactor1315]

Has this tank finished cycling? Putting anything especially sea horses in a tank with ammonia in it is just asking for problems. You should stabilize the water and figure out where these problems are comig from instead of putting media to remove the aftermath of the problem.

 

[ras2883]

Hi Tony,
Thanks for your reply.
Yes the ammonia was .25 for some time, as far as feeding I only feed live fresh hatched brine shrimp or copepods, I thought they would remove any excess ammonia.
Do you think my idea of using a mix of activated carbon and ammonia absorbing material in the filter work to prevent any further spikes?

 

[ras2883]

Hi Xfactor,
Yes I believe the tank had finished cycling.
I am still trying to figure out what caused the death of the fishes in the first place.

 

[gone fishin]

Lets start this way how long has the tank been set up.
If not very long then it is still cycling.

I am not very familiar with seahorses. I believe the are pretty delicate and sloppy eaters. You may want to check out the seahorse section for more expert opinions.

Mandarins are very picky eaters and again I don't have actual experience with them other than my research. I think it would be a difficult task to keep them in a 10g supplied with pods.

 

[ras2883]

Hi Tony.
I have had this tank for about 2 months.
During which I had the live rock and live sand in it.
I cycled it for 1.5 months before I put my first fish.

 

[gone fishin]

It does sound like you are getting some die off. If your mandarin is still alive along with all your seahorses, then the only thing I can think is to much food in the tank. I do believe you have started out with some very tough specimens. I would run your carbon and maybe put in some amquel to bring down the ammonia and some water changes. Again a 10 gallon can be very difficult for someone starting out. If possible maybe you could get a 20 or 30g. The more water volume you have the more stable the tank will be. I would definately do more research on your choices and head over to the seahorse forum for some tips. good luck to you

 

[ras2883]

Hi Tony.
I have had this tank for about 2 months.
During which I had the live rock and live sand in it.
I cycled it for 1.5 months before I put my first fish.

 

[ReeferKimberly]

Doesn't sound like it finished cycling if it had any ammonia. Should always remain at 0. A brand new tank with seahorses and a mandarin.....well I certainly wouldn't ever bet on it. I believe they died because there was ammonia. One of them could not handle it. When it died it caused even more ammonia and they all went down. It's either that or some mechanical or chemical failure for them all to die overnight. A heater malfunction or overdose of something. But I am betting on them all being compromised from the ongoing ammonia and then the first one's dead body started the domino effect.

A 10 needs to have a very low bio-load to keep stable clean water. 5 seahorses, a mandarin, some shrimp and snails is probably going to be too much for it to handle. You didn't mention....do you have a sump or refugium or anything else to add water volume? If not, then it's really not even 10 gallons. Counting sand and rock it's gonna be like 6 or 7 or something like that. That's a big bio-load for 6-7 gallons of water.

 

[bertoni]

I would get a second opinion on the ammonia test kit. I agree that 0.25 ppm can be toxic, but sometimes kits fail and read a bit of ammonia everywhere.

It's possible that a quick ammonia spike killed a number of fish, and the tank processed the ammonia before you took the measurement.

 

[bertoni]

I would get a second opinion on the ammonia test kit. I agree that 0.25 ppm can be toxic, but sometimes kits fail and read a bit of ammonia everywhere.

It's possible that a quick ammonia spike killed a number of fish, and the tank processed the ammonia before you took the measurement.