Black Spots

[BacardiXx]

Dear Fish hobbyists,
 
I just got an tropical aquarium for a month now, and i must say it is really peacefull. 
its fun on spending time on your aquarium , taking care of the fishes.
 
But i think my fish got a sickness or something like this, maybe on of you can help me out what exactly is going on with my fish.
I started to put fish in my aquarium about 1 week ago,  the aqarium was already been setup for 3 weeks and the quality and temperature was superb of the water.
Now because i already had this water for 3 weeks running i just refreshed the water for 20% yesterday. 
 
The fish store also adviced to take an conditionneur after the water refresh so the water quality will still be good. ( on the manual it says 10 ml per 30 liter, i 
got an 60 litre aquarium but i only threw in 10 ml).
also cleaned my filter in the old aquarium water wich i take out so i still have the good bacteria after the water refresh.
 
now today i noticed one of my fishes are gone ( an cardinal tetra ) and my fishes got black spots over their skin, it is not deep dark but it is strange.
They do act normal and the ph looks good after a measurement,
 
i got in my aquarium: 
Betta Splendens
5 Cardinal Tetra ( 1 died, didn't find anything in or around the aquarium )
3 Corydoras Panda
2 Ghost Shrimp
 
Here is a photo of the tetra with black spot, sorry that the photo is not good quality. ( 300 kb max 

)

 
can maybe someone say what the black spot is?
thanks for advance!
 
Bjorn
 

Here by an link to some more photos
http/imageshack.us/g/1/10239489/

 

[ncguppy830]

what are your water readings?
possibly neon tetra disease but i need clearer pics

 

[BacardiXx]

Ph is 6.5 and temp 24 or you need other water readings?
here are some other photo's. its not only the tetra's wich got it, my cory got the same.
still hard to see, sorry for that. Fish had a great time swimming haha xD

as you can see behind his natural black spot it should be white.
 

 

 
on his head
 
and here is the conditionneur

 

[Blondielovesfish]

By other readings I think he means ammonia, nitrite and nitrate.
Was the tank cycled?

 

[DoubleDutch]

The cardinal at the right side isn't good at all I think. I see a colorloss I think??? This could mean NTD or more often false NTD (Columnaris bacteria). Don't actually know what I am looking at with the Panda. Is it a whitish layer on it ?

 

[BacardiXx]

thanks for response!
to >Blondielovesfish
the aquarium has not been cycled very well i think, because i never knew this process untill yesterday when i did read your CYCLING - ALL BEGINNERS READ THIS
when i bought this aquarium the local fish salesman told me to put some nitrivec in the aquarium then wait 2 - 3 weeks , after that i came back he checked my aquarium water
and he said it was ok.
now today i did get some test and the readings are as following:
cl2: 0
ph = 6.8
kh = 6 
gh= 7
nitrate = 25
nitrite= 0
couldnt measure ammoniac
 
to > doubledutch
yeah sorry you dont see it very well, today it got worse and yes they get less color it seems. yesterday night one tetra wasnt glowing at all.
and with the cory you see just some black things behind his eye, dont see it very well but all corries got it and didnt have before.
you can see on the second photo of the corry also a black spot on his head.
was just white 

 

[This Old Spouse]

You absolutely must get an ammonia reading. How did you cycle your tank? Was it just with the product or did you dose ammonia? 

 

[BacardiXx]

dont have any atm, waiting for my chip for my seneye to do a ammonia reading , but the fish shop gets this next friday.
i only used Sera Nitrivec wich says the following on the description:
sera nitrevec breaks through the cleansing bacteria contained therein ammonium and nitrite.
removes harmful substances, binds opacities in an effective way and provides the cleaning bacteria a residence area.
makes placing fish after 24 hours possible.
 
also my betta does not seem to have any problem at all, 

 

[Blondielovesfish]

most of those "bacteria in a bottle" kind of things don't work - except for a few.
Until you get your test kit I would recommend that you do daily water changes of 50% (at least, feel free to do up to 90%). Make sure to use dechlorinater and match the temperature.

 

[BacardiXx]

So after some research etc, i have found out what is the issue.
it seems it is a paracite, my fish are also shaving the skin against plants and stuff.
ive been to the local aquarium seller and he did found an unicellular parasite at the tetra that i took with me.
he advised me to take protazol to take care of this. My Seneye readings also said i only got 0.015 ammonia

 

[Blondielovesfish]

Glad you found out what was wrong!
I hope it gets cured