What is wrong with my guppies

[civprod]

I have a 55 gallon tank. I did a fishless cycle first and then have slowly been adding fish.

Right now, the tank has 6 black skirt tetras, 6 mollies, 7 fancy guppies and 5 hatchetfish.

The guppies are the most recent addition (I got them on Friday). I got 4 male and 4 female.

I had one female guppy die overnight (it had been listless and just floating near the top the entire day before). Before it died it was not really swimming or anything, it was just floating. It's tail also looked like it was torn.

I have another female guppy that has the same symptoms right now. It also looks like she has a torn tail, and she is staying near the top all day. She has been swimming some but it is not a normal swimming motion (I ould imagine because of the tail). I have a feeling that she is going to die.

None of the other female guppies or any of the other guppies appear to have any problems whatsoever. I have been paying close attention to their behavior and they are all swimming normally and their tails look fine. The rest of the guppies are active. There is one other female guppy that spends time near the top but I don't believe that it is the same kind of behavior as she is still swimming around alot and her tail looks fine. It just appears more that she is resting near the top instead of down lower.

None of the other fish in the tank appear to be having any problems. They are displaying a normal level of activity.

I have checked all my water levels. They have been reading 0 ammonia and 0 nitrites and very very low nitrates. I am using an API master test kit. I don't think that the issue is water related.

To answer some potential questions:
(1) I did not quarantine the guppies prior to adding them to the tank.
(2) I have not observed any of the the fish attackign the guppies or anything that could explain the fins. It is my understanding that all of those fish can co-exist.
(3) The guppies appeared to be acting normally when I added them to the tank and right after they were added. It was not until Sunday that I noticed any sort of problems and even then it is only with two of them.

Can anyone give me an idea of what is going on? Should I try and take out the other guppies? Also, since I don't have a quarantine tank and there is no place to get one at this time, if I need to tank them out, what should I put them in?

Thanks.

[THE V]

Sounds like a bacterial infection causing finrot to me. Kind of hard to tell without pictures. Keeping your water conditions pristine can keep it from spreading to others but you may have to treat the tank.

You really should quarantine your fish prior to adding them in. 5 gallon bucket with a sponge around an airstone is much cheaper than the meds for treating a disease.

[civprod]

I tried to get a picture of the fish but I couldn't get a good one that showed the detail of the tail.

If I get medicine for the tank tomorrow, is fin rot curable or is the damage to the fin permanent and the fish will never be normal again?

Also, would I be better off pulling out the remaining female guppies and putting them in something like a large pot or a pitcher (I have no better option at the moment, that will be changing though, along with medicine I am going to get a small cheap tank).

[THE V]

Once you get the cause of the finrot taken care many types of fin damage will heal in time. I would leave the guppies in the main tank for now if you don't have the proper setup for quarantine yet. Putting them into a pot or pitcher will stress them and may lead to more deaths. Just get to the store as soon as you can to get the meds. You can also take the fish back to the store you bought them at for a refund as they sold you sick fish.

[cbau45]

If it is a bacterial infection then they likely had it when you got them. The reason I say this is because bacteria attacks from the inside out. The other question I would ask is what is your male to female guppy ratio. Sometimes the males can harass the females, especially if there are more males than females in the tank. However, I tend to lean towards the bacterial infection as well, most likely finrot.

[civprod]

Before the one fish died yesterday, it was a 1:1 female to male ratio.

[terror spawnin]

I'd say the mollies are working on them when you are not looking. Likely after dark. With torn fins and surfacing it really sounds like exhausted submission.

I also wonder why it could seem like fin rot if the fin is torn.

The aggressor will pick off one at a time until only the quickest males are left!

[doreenjoy]

In my experience, both mollies and black skirt tetras are potential fin nippers.

[terror spawnin]

Makes sense..piranha's are tetras too!!!

[Lupin]

Makes sense..piranha's are tetras too!!!
They're not tetras but rather Serrasalmus. They still fall under Characins category.

[terror spawnin]

They're not tetras but rather Serrasalmus. They still fall under Characins category.
I have read about piranhas being related to tetras and I've also read the wikapedia version wich does not contradict this..it just does not mention it.

Either way I agree with doreenjoy.

[KarlTh]

I have read about piranhas being related to tetras and I've also read the wikapedia version wich does not contradict this..it just does not mention it.

Either way I agree with doreenjoy.

Tetras and Piranhas are both in the Characidae family, but whilst tetras belong to the subfamily Tetragonopterinae (African tetras are Alestiinae), the Piranhas, along with Pacu and Silver Dollars, are in the Serrasalminae.

So think of it as South American tetras being siblings, with the African tetras and Piranhas as cousins.

[civprod]

I have tried getting pictures of it so that it would be more obvious what I am talking about but I was not able to get any good pictures.

I do not know if torn is the right word to describe the damage to the tail. The tail is not missing any pieces, which I would think would be the case if they were being nipped by I could be wrong. Instead, it almost looks like the area between the spines in the tail fin has disappeared, just leaving the spines themselves. However, I can't say for sure whether or not the fin between the spines is gone because the tail is clear and I have not been able to tell for sure.

Also, when I woke up today and went to check on the fish, I could not find any sign of it. I did not have too long to look for it so it could still be there but I didn't see it anywhere. I am going to look some more when I get home. I know that it is possible that the other fish ate it, but would the entire thing really be gone in approximately 8 hours? Also, if the other fish did eat it, wouldn't that be unusual as these are all supposed to be tropical community fish and everything I read seems to suggest that they should coexist with each other?

Finally, if nipping is the problem, what can I do to help protect the other fish. I have some caves and plants on the bottom of the tank and then I have some other plants and cover near the waterline, so it seems like there should be plenty of places to get cover.

[dixienut]

i have black skirt tetras in with smaller fish and they don't bother anyone but eachother, never went after platties or neons or ember tetras or cherry barbs so if anything it could be mollies, but have never owned one of those so only guessing,..