Something In My Water?

[Demeter32]

Hello everyone, new to fish forums but not to aquariums. I have 7 zebra danios, 2 Cory cats, one brittle nose, male half moon betta and a female paradise gourami in a planted 20gal tank. I first notices that my zebras were having trouble breathing and hanging around the surface. I investigated and assumed it was a case of flukes seeing as their gills seemed inflamed. So I removed the danios and placed them in a quarantine tank and treated them for flukes. All went well and they recovered. Then I noticed the 2 corydoras had split fins but otherwise seemed fine.
I returned the zebras to the 20gal but by the end of the day they were laying on the bottom of the tank, listless.
I put them back into the quarantine tank and they seem much better and visually unharmed. I made a 50% water change and added "start zyme" fizz tabs. To be sure the water was ok, I returned one of the danios to the 20gal and waited. Now both my danio and my betta are gasping at the surface and listless. So I put both in the quarantine tank.
There are no visual issues other than the split fins. The danios seemed to have red inflamed gills when in the 20gal but not in the quarantine tank. The brittlenose is an angel and very docile as well as unharmed.
I am unable to test the water parameters at the moment but I've never had a problem like this before. The water I use is well water, no chemicals of any sort added other than the stress coat. I make weekly water changes and the tank is cycled.
I know this is a bit jumbled but I'm on the verge of panicking and this is my last resort. Plz help!

 

[nic1]

Hello, welcome to the forum.
If they seem ok in quarantine then it's definitely a water issue in the main tank.
Possibly ammonia as red gills are an indication.
As you have already carried out a half tank water change I would do a 90% change leave the fish in the Q tank and let them get their strength back, try and buy a water test kit in the meantime so you can see what exactly is going on in the main tank,


Do you also have an air stone? Would be wise to get one to add oxygen to the water...
Also, vacuum the substrate really well.

 

[the_lock_man]

Everything you say points to ammonia and/or nitrite poisoning. You need to get the water tested ASAP.
 
How long has the tank been set up, and how did you cycle its filter?

 

[Demeter32]

Oh wow this was a heck of a long time ago. I forgot I even had an account for this site until i decided to check it out again. Looking back now I seemed pretty dumb. I am so sorry you all had to see that

That tank has long since been replaced by a 55gal full of Africans and I used the 20 gal for raising their first batch i fry I got from them and NOW THOSE LITTLE BABIES ARE MAKING THEIR OWN LITTLE ONES

 

  I still have 3 of the zebra danios in a 29 along with the paradise gourami (who is actually a male) The cory cats are in a 10gal with a male betta and the pleco is with the Africans 

 
Just to show off:
Male yellow lab/peacock hybrid

 
Female yellow lab/peacock hybrid (holding)

 
The daddy of the hybrids 

 

[HarpyFishLover]

We all learn some time...

 

[NickAu]

Bettas and Gouramis should not be kept in the same tank.

 

[Demeter32]

No worries mate, that was 2 years ago If you check the dates it says it all. In the end the water problem was solved via lots of water changes