Black patches on Three-lined pencilfish (Nannostomus trifasciatus)

[asti015]

Hi guys,

I am new to this forum as i've been looking for some information regarding the little pencilfish guys that i have and this forum came up on google search with a few entries, so i was hoping someone can help me.

I was wondering if anyone knows what their lifespan is?

Also one of my guys has developed a black patch around the tail area. I have seen this before a few times on my old tetras and have always thought it was due to old age or maybe some kind of cancer, but my pencil fish are 2.5 years old (that i have had them for) so if i assume they might have been around 6 months old when i bought them they shouldn't be much more than 3. Im not sure if this is old for them or not, hence the lifespan question, but i think it shouldn't be? Im in New Zealand and these guys are relatively new here, so noone in the fish shop seems to have any detailed information on them.

If anyone can help me with figuring out what the black patch is, or how long they live for that would be really great!

Thanks
asti

[Quixotic]

The lifespan could be up to 5 years or more, comparing with tetras of the same size, but these are merely guessworks.

Do you have a good picture? It's hard to diagnose something based on limited information and visualisation.

The best guess would be that these black patches could be bacterial infections. If you could get Melafix in NZ, it may help. Melafix is useful in open wounds and abrasions, and promotes regrowth of damaged fins.

[asti015]

Ah ok thanks, so they should be able to go for about 2 more years..

I have a pic but its not very good. The problem is that the patch looks like its a part of the fish, and doesn't look like a bacterial infection or antyhing i could match up by going through fish diseases.

So the black patch is on the end of the body just before the tail starts.





The patch is not moving, spreding, getting larger.. just stays as it is. The little guy hasen't been acting any differently than usual. He/she is active, scools with the rest of the guys, is eating.. (and was extremely upset i put him in the glass to take pics of him).

We can get melafix in nz, and i have used it before but i haven't found it very effective (and its extremely expensive). But if you really think it will help i will buy some. My fishies only get the best (and dogs and birds and the cat.. and people wonder why im broke all the time, hehe).

So any help is appreciated, as i would like to keep him. Here they're pretty expensive and hard to come by..

[Quixotic]

It's difficult to tell from your pictures, but looks like it is more on the body rather than the fins. I think those may be red patches but could have darken over time.

I previously had a batch of Nannostomus mortenthaleri which show similar symptoms, except that they manifested as red patches that gradually turn rather dark. Unfortunately, I did not have much success in treating them using Melafix.

Melafix was suggested because conclusive diagnosis isn't possible and it is good for healing external wounds, rather than risking the fishes by getting specific medication when the disease couldn't be properly identified. Perhaps as a stop gap measure?

Making an educated guess, it could be this, http://www.aquaticquotient.com/forum...3&postcount=18

Assuming that this is the case, then it could indeed be bacterial infection as I previously suspected. However, I am not sure what medication could be used, perhaps your LFS would be able to advise, or wait for a second opinion from our members.

In the mean time, stay on top of your water conditions. Good water conditions will promote healing capabilities.

Yeah, I understand that fishes are really expensive over there in NZ. And yet, we in Singapore here are complaining while we are spoilt on choice and blessed with much cheaper pricing.

[asti015]

Ok thanks a lot. I have checked my water and my water conditions are good. There's quite a few fish in the tank and i have seen this happen before, but it never spreads or affects other fish.

The patch is on the body, just before the tail starts. It hasen't been getting larger or spreading on the fish... i think he had it for at least a week now. It wasn't red to begin with (unless it changed colour very quickly).

I will treat the fish with some antibacterial medication and see if that helps. Thanks a lot for your help. I wish i could get a better pic, but he's very active and for some reason i can take as many pics as i want from any one of his friends, just not him.. lol

Oh also, it's on both sides of him. Kinda looks like someone dipped him in dye tail first, but the fins didnt get dyed.. if that makes sense. He still has the shiny white patch on the tail (the fin) so its only about 0.5 cm from where the tail fin starts towards the body, that is darker.. funny thing is that the black lines are still darker than the black patch as well ...
asti

[asti015]

Hi guys,

So regarding my pencil fish. I have treated him for bacterial infection, but this made absolutely no difference..

However, it is defenetly not part of his colouring as he lost colour during being stressed out from giving him the 'bath' and it looks like the skin is black or maybe it's the scales. This morning he looked same as usual.

Does anyone else have any ideas? Any suggestions welcome.

I also went to the fish shop and they didn't have any ideas of what it could be either...

asti