Shrinking Tail on Zebra Danios

[Kingzilla]

I have 1 Zebra Danio (his friends died) and 3 White Cloud in my 20gal tank right now. I put the Zebra in quarantine by means of a breeder attached inside the aquarium with suction cups to rule out bullying from other fish but his condition has gotten worse and the other fish are starting to show symptoms.

What's happening is that the tail fin starts to narrow until the back is the same height as the front of the fin. This has started on 2 of my white cloud. As for my zebra, after this, part of his tail went missing (hence the isolation) and I have ruled out abuse from other fish as the cause because his tail fin has gotten worse. I should add that I haven't noticed any other symptoms besides the til fin.

here is a sketch (excuse my poor drawing abilities) of what the tail does

what could be causing this and how can I treat it?
any help would be appreciated

 

[LyndaB]

What are your readings for ammonia, nitrite and nitrate?

Any changes made recently to the tank?

 

[Kingzilla]

ammo is 0.25ppm
nitrite is 0ppm
nitrate is 5ppm
pH is 7.9
Temp is 25C
no recent changes

 

[LyndaB]

Ok, the tank is not cycled. How long has the tank been up? How did you cycle it? With the fish?

 

[Kingzilla]

I should add that my tank water constantly tests identical to my tap water and I'm using both the API freshwater master test kit and the 5in1 and ammo test strips from API.
I never get the test chemicals near the aquarium, I don't even test in the same room and I do not fill the test tubes in the aquarium, I use a separate container for taking water from the aquarium.
Sorry, I just wanted to completely rule that out as a possibility as I'm very careful.

 

[LyndaB]

What are you using as a dechlorinator?

I would not put your tank water in a container and then fill the test tubes. It's possible that you could cross contaminate that way. Just dunk the tubes into the tank.

Forget the strips, they're worthless. Glad you have the API master kit.

How long has the tank been up and how did you cycle it?

 

[Kingzilla]

it's been running about a month, I'm seeding with used filter media. if you remember on the general discussion forum, I had the thread about a new tank with rapid death rate.

i let the tank run for 96hrs before putting the first fish in but all those fish are dead from unknown causes but I may be onto the issue here.
my zebra is about 2 weeks and the white cloud re 1 week today

 

[Kingzilla]

I was using prime but switched back to LFS brand for a few WC to compare test results.

it's a dedicated container for testing water, I wouldn't dare put the tubes in the tank as the test chemicals are highly toxic.

test strips are actually accurate, their bad reputation comes from the majority of people that use them wrong. don't get me wrong, liquid test are better but strips still give good results when used properly.

 

[LyndaB]

After you take the tests, you should be thoroughly rinsing out the test tubes. There's no reason to think that they are toxic to your tank, if cleaned after use. But do what makes you comfortable. If you are not rinsing them out after use, you're going to get faulty readings.

Just a though, but if it was my new tank, I don't think I would've been experimenting with different dechlorinators to see what results you get. I can see after you have a stablized tank, but not when it's first set up.

How often are you doing water changes? Fin rot, and that's what it seems it is to me so far, is easily treatable and reversable with healthy water changes.

I have to admit that I do not remember your initial thread as I'm involved with dozens of threads each day. Sorry.

 

[Kingzilla]

I do rinse them but better safe then sorry.

I was originally using LFS brand but everyone said to switch to Prime so I did but as it does stuff to what I'm trying to test, and that my results were a little confusing I went back to LFS brand. unless the tank is cycled, shouldn't there be more ammo in the tank then in the tap water?

I was doing daily WC but for the last few days I've been doing WC every other day since changing the water wont lower the ammo or nitrate levels as they are the same in tank and from tap.

as for fin rot, does that attack all fins or only tail fins as all other fins appear normal

 

[LyndaB]

Fin rot seems to start with tail fins but it can affect others.

I don't understand what you mean by Prime does stuff to what you're trying to test.....

Even with ammonia in your tap water, you should not get an ammonia reading in your tank. That's what the dechlorinator does.

I should add that many people have said that testing within 24 hours of using a dechlorinator can also give you false readings. Not sure if that may fall into what you're finding.

 

[Kingzilla]

I don't have the bottle on hand to quote right now but it removes ammo, and detoxifies NO2 and NO3 (or something along those lines) whereas a standard dechlorinator does not

and if you cant test for 24hrs, testing when doing daily WC would prove ineffective

I guess I'll pick up some medication for fin rot on my way home and go back to daily WC... Is fin rot contagious?

 

[LyndaB]

It depends on the cause of the fin rot. You don't need meds for it, you just need clean water. If it's affecting many fish, it's the water. As for the Prime, you WANT it to detoxify. You're still going to get appropriate readings.

 

[Kingzilla]

I'd rather go with meds as the water should have been fine in the first place... I've had too many fish die (14 guppies and 2 zebras to be exact) to take any chances but atleast the death rate has decreased, it went from dead within 24hrs to my record setting zebra in critical condition at 2weeks. Now my white cloud are following in the zebras footsteps.
Here's the link to the other thread, maybe a quick peek might refresh your memory but I think this might be connected http://www.aquariumadvice.com/forums/f15/new-tank-with-rapid-death-rate-199576.html

WC alone won't be enough. Is there a good broad spectrum medication that treats fin rot?

 

[LyndaB]

I can't refer you to one med over another as I don't use meds in my tanks.

Ok, I just read your entire other thread through again. I think instead of starting a new thread like you did here, you should ask a moderator if they can attach this thread to your other one. There's too much history there that would be lost with this thread standing alone.

I had forgotten about your temperature issues and possible poor stock. That really does add to the stress that these fish went through being used to cycle a tank.

Your tank appears to be a mystery. Not sure why.

 

[Kingzilla]

temp was only an issue for about 3 days due to unseasonal warm weather and only the zebra experienced that. My gf just texted me saying fin rot so she got advice from somewhere else and got the same answer so I'm going to attempt treating for that. The person told her that the filter needs to be changed, is this true?

 

[Kingzilla]

LyndaB, I meant to say it in my last post but got distracted, thank you for the effort of actually reading the other thread, I didn't intend for that, but thanks for actually putting in that kind of effort to help, I greatly appreciate it

 

[LyndaB]

You're welcome.

The filter has nothing to do with fin rot, in that sense. As long as you're getting good water flow through it and it's not clogged, the filter itself and the media are not the issue. Shame on that person for even advising that. It's just dumb.

 

[Kingzilla]

that's what I thought, the only thing I could think of was that it would hold the disease but changing it would fail as it would be in the water so the new filter would become infected anyway

 

[emerald76]

Id guess it's ammonia, I had the same problem