5 replies to this topic

[DiscusDreaming]

Hi Everyone,

I am a bit of a newbie and this is my first post, so please be gentle...

I have a 120L planted tank that is home to the following fish stock:

2 x Clown Loaches (approx 5cm)
8 x Harlequin Rasboras
2 x Twig Catfish
8 x Cardinal Tetra

I'm pretty sure that something in my tank is nipping at my Cardinal Tetra. I've been losing 2 per day over the last couple of days.

My first thought was that I may have some problems with the levels in my tank or maybe a parasite or disease. The Tetras will have a whiteness to parts of their body and have troubles swimming, then will die in the next few hours.

This morning I noticed one of my Tetras was having real difficulty swimming, and upon closer inspection it seem like part of its tail is missing. Being the largest fish in my tank, my assumption is that the Loaches are the culprits. But my Harlequin Rasbora seem to generally dominate the tank, they swim around happily and energetically, while the Tetras tend to huddle in a corner and not explore the tank much at all.

Any help would be greatly appreciated :-)

*I can also provide pictures or videos if it might help*

[Juls]

I don't think the problem is something is nipping your cardinals, I feel that you have some kind of tetra disease in the tank, and as each tetra starts to succumb the other fish in the tank notice the struggling fish and start to nip at it, which is perfectly normal behavior regardless of the type of fish.

The other remaining tetras and the rasboras will start to nip at any fish thats struggling health wise, eventually the clown loaches would have a go too.

I doubt the clowns would do anything much while they are still so small though until the other fish actually is dead, Although I would suggest considering a smaller type of loach as you don't have space in that tank for even one clown loach long term. (they will reach 20-30cm in size, should hit 15cm within 18 months or less).

Cardinal tetras are not the most exciting tetra when it comes to movement or schooling type behaviour, they tend to wander aimlessly singular or in pairs during the day, then at night time after the lights go out they will group back up, they won't school properly unless they feel like they are in danger.

The rasboras are far more active and exciting as you have found, only the rummy nose tetra will give you that constant schooling action, although only when a larger fish is around, (like a discus or angel).

Anyway back on topic, if your losing tetras every few days it may be worthwhile separating the tetras from the rest of the tank until the problem sorts itself out, best to remove any fish that have or are dying immediately as the dead body may give the other fish in the tank the illness too as they eat at it.

Juls

[DiscusDreaming]

Thanks for the advice Juls,

I will move the tetras out straight away. I've added a few images of what the tetras are looking like. Do you have any idea what sort of disease might be effecting them? Is there any treatment that I should add / perform to the tank?

Once again, any help would be greatly appreciated :-)

Attached Files

•  DSCF2401.jpg   28.72KB   36 downloads
•  DSCF2410_2.jpg   21.94KB   34 downloads
•  DSCF2413.jpg   27.15KB   45 downloads

[sydad]

While accurate diagnosis is always difficult from photos, I feel reasonably certain that your fishes are displaying infection signs of both white spot, and Neon Tetra disease. While the former is treatable, the latter is not, and any fish displaying an opaque whitening of the tissues, particularly in the tail region, should be considered infected, and either isolated or destroyed.
If an infected fish dies in tha aquarium, and is not removed before dissolution, or is consumed wholly or partially by tankmates, no new uninfected stock should be added for ar least 6 weeks. Ideally, an aquarium that has housed fish known to be infected with neon disease, should be torn down, thoroughly cleaned, and reset.Plants may be reused after disinfecting with alum, hypochlorite or potassium permanganate(Condy's crystals), though there is no guarantee that they will survive the treatment. or indeed that all infecting organisms are destroyed.
Sorry to be the bearer of bad news, but at least you will be aware of the existance of the disease: and ALWAYS avoid neons and cardinals that show any sign of colour loss/opacity in the area behind the abdomen.

Syd.

[DiscusDreaming]

Thanks for your help Syd and Juls!!

I've taken all your advice on board and along with recommendations from my LFS this is the treatment I have gone with:

1. Removed all fish from the tank and treated with the Ichonex, Tri-Sulfa and an Antibiotic.
2. Removed all plants and rinsed with potassium permanganate.
3. 50% water change to tank, replaced all substrate with new. Replanted plants.
4. Checked all levels today (which were all good) then added the fish back to my main tank and retreated with Ichonex, Tri-Sulfa and Antibiotic.

I won't be adding any new fish to the tank until I am 100% sure everything is under control again. (probably at least 6 weeks)



Thanks again for your help.

[meganj]

Good luck! Keep us posted how it's going.