Dying rummynose tetras and kuhlis

[Zebrakat]

I have a cycled 360l aquarium with kuhli loaches, Cosby gouramis, plecos and snails. This Friday I added 20 rummynose tetras. I bought them from my LFS which is highly regarded around here as having good stock and being safe to buy from (and giving good advice etc).
Starting yesterday they began dying. 2 disappeared completely (most likely eaten as I found a very small piece that’s probably from one). 1 suddenly had bulging eyes and swam upside down for around 20-30 minutes before dying. 1 I found floating at the top of the tank this morning.
As I was watching the tank around half an hour ago, one of my kuhlis suddenly laid down at the bottom and died, very peacefully (Or so it seemed).

Currently all fish are swimming fine but I would of course like to find out if the problem is simply due to stress from the move or if I should/can do something to prevent more deaths.
I have found one tetra with a white patch right in front of its fin but none of the dead ones had that. Another is sort of pale right behind its head. I’ll attach pictures.

I have treated the tank with esta 2000 as it should be effective against a variety of problems and it can be quite hard to get medication for fish in Denmark. (So it might take a while to get a hold of it even if I find out what I should use)

Tank size: 360l
pH: 7,3
ammonia: not available in my test kit
nitrite: 0
nitrate: 0
kH: 15
gH: >21 (kH and gH is normal for my area and thus also for the LFS, fish generally live fine despite it being in the bad zones on the test kit)
tank temp: 25 degrees Celsius

Fish Symptoms (include full description including lesion, color, location, fish behavior):
1 tetra died with no signs on its body
1 died with bulging eyes after swimming upside down
2 just disappeared
1 kuhli slowly swam along the bottom, stopped at a point and died.

Volume and Frequency of water changes: around 25% every week

Chemical Additives or Media in your tank: HappyCarbo, easy-life profito, algin-regular

Tank inhabitants:
16 (now 15) kuhli loaches
5 coby gouramis
3 amano shrimp
3 rabbit snails
10 Nerite snails
2 plecos (ancistrus)
20 (now 16) rummynose tetra - added this Friday

Recent additions to your tank (living or decoration): 20 rummynose tetra, 2 tropica plants

Exposure to chemicals: HappyCarbo, easy-life profito, algin-regular

Digital photo (include if possible):

 

[Colin_T]

Chemical Additives or Media in your tank: HappyCarbo, easy-life profito, algin-regular

no idea what they are but you should try to avoid putting things in tanks if they are chemicals or kill algae.

-------------------
The fish appears to have a bacterial infection and that is probably what killed the others. You can try a broad spectrum fish medication that treats bacteria, fungus and protozoan infections. Other than that antibiotics, which you probably can't get.

Before you treat the tank, do the following things.
Work out the volume of water in the tank:
measure length x width x height in cm.
divide by 1000.
= volume in litres.
When you measure the height, measure from the top of the substrate to the top of the water level.
You can use a permanent marker to draw a line on the tank at the water level and put down how many litres are in the tank at that level.

There is a calculator/ converter in the "FishForum.net Calculator" under "Useful Links" at the bottom of this page that will let you convert litres to gallons if you need it.

Remove carbon from the filter before treating or it will adsorb the medication and stop it working.

Wipe the inside of the glass down with a clean fish sponge.

Do a 75% water change and gravel clean the substrate. The water changes and gravel cleaning will reduce the number of disease organisms in the water and provide a cleaner environment for the fish to recover in.
Make sure any new water is free of chlorine/ chloramine before it is added to the tank.

Clean the filter if it hasn't been done in the last 2 weeks. However, if the filter is less than 6 weeks old, do not clean it. Wash filter materials/ media in a bucket of tank water and re-use them. Tip the bucket of dirty water on the garden/ lawn.

Increase surface turbulence/ aeration when using medications because they reduce the dissolved oxygen in the water.

 

[Zebrakat]

no idea what they are but you should try to avoid putting things in tanks if they are chemicals or kill algae.

They are liquid co2, fertilizers and something which should reduce algae but be safe for the fish. I guess maybe I shouldn’t use the algae one anymore then?

I will keep treating with esha 2000 then. It should work against most bacteria, protozoan infections and fungi.
I did a water change before the first treatment, however just a normal one. I’ll do a 75% one tomorrow before the second part of the treatment.
The filter was installed with completely new filter materials around 8 weeks ago and has been cleaned around 3 weeks ago so I’ll probably leave most of the material alone.

Thank you very much for your explanations and suggestions. I will get started right away.

 

[Salty&Onion]

Don't use such chemicals such as the algae killers and liquid CO2 as they will most likely to harm your livestock. Any small overdose of the "liquid" CO2 will hurt or kill.

 

[Zebrakat]

Don't use such chemicals such as the algae killers and liquid CO2 as they will most likely to harm your livestock. Any small overdose of the "liquid" CO2 will hurt or kill.

I will avoid them in the future.
However, they are well known and used by many without problems so I’m quite surprised that they’re that dangerous

 

[seangee]

Liquid CO2 is poison (gluteraldehyde) and the recommended dosages are carefully calculated not to kill fish too quickly. I won't use it for the same reason I won't put cyanide in my food - that is supposedly also "safe" for human consumption at sufficiently low dosages.

I'm afraid GH of 21 is not fine for softwater fish. They will have very short and unhealthy lives. They have evolved over 1000s of years to live in soft water and an excess of minerals leads to premature kidney failure as they are unable to remove these minerals from their bodies. The fish shop only has to keep them alive for a few weeks and will never tell you how many they lose. I also live in a hard water area and my LFS loses more than 50% of the fish they bring in.

 

[Zebrakat]

I will refrain from using it from now on. Thank you

 

[CassCats]

Im also wondering if adding 20 fish at once caused an ammonia spike, which would stress fish, if not kill them, and can cause secondary issues like bacterial infections.

Rummies are sensitive to spikes and so are kuhlis, so it would make sense theyre the first to show problems

Treat the secondary issues like Colin says and do the water changes daily until things return to normal

 

[Zebrakat]

I was told it would be fine due to the size of the aquarium and that it had been running with fish for a while already.
But I’ll probably fewer next time I add fish, just in case.

I’ll keep up with the water changes and continue the treatment. Thank you very much for the help

 

[CassCats]

I was told it would be fine due to the size of the aquarium and that it had been running with fish for a while already.
But I’ll probably fewer next time I add fish, just in case.

I’ll keep up with the water changes and continue the treatment. Thank you very much for the help

Yes that many rummies would be fine, but added in smaller numbers over a few weeks to let the beneficial bacteria catch up to the new added bioload. Large numbers added all at one time overwhelm your good bacteria in your tank. So its suggested to add a couple at a time. Start with 6. Wait a bit. Add another 6. Wait a bit. So on. Even adding 6 of some species can cause a spike.

 

[Essjay]

I would not get any more rummy noses, though, as they are soft water fish. As @seangee has already explained, your water is too hard for them - and any other soft water fish.

 

[Byron]

I agree with other members on not using the chemicals. And on the water hardness issues.

A general comment on adding new fish when you next do...as you have live plants, you do not need to worry as much. Shoaling fish (fish that need a group of their species) should always be added together at the intended number. They will settle in faster, which means less opportunity for ich or similar.

 

[Zebrakat]

Okay I will keep that in mind

 

[Retired Viking]

I agree with the others, If you want soft water fish I suggest you do what I do and use RO water. My water is moderately hard so I add RO water (reverse osmosis) to soften it down for my tetras. It is more work lugging around 5 gallon jugs and mixing it but I like my little tetras. I keep both hard water and soft water fish in their own tanks.