Black Stain on baby Asian Arowana

[Alf23]

Have you tested your water?

No

If yes, what is your ammonia?

0.0

If yes, what is your nitrite?

0.0

If yes, what is your nitrate?

Normal

If I did not test my water...

1. ...I recognize that I will likely be asked to do a test, and that water tests are critical for solving freshwater health problems.

Do you do water changes?

Yes

What percentage of water do you change?

31-40%

How frequently do you change your water?

Every week

If I do not change my water...

1. ...I recognize that I will likely be recommended to do a water change, and water changes are critical for preventing future freshwater health problems.

Hi there, please let me join this forum!

So i just got 4" (10cm) baby asian arowana, when he first came his body just fine! But after one day, black spots appeared on his back.

what should i do now?
Is this disease dangerous?

 

[Alf23]

There is a little bit mistake, yes! I have tested my Water the PH at 7 too. ?

 

[Caveden]

Could it be just dried slimecoat? I rmbred a video from king of diy where his arowana had dried up slimecoat which was black in colour

 

[Alf23]

Could it be just dried slimecoat? I rmbred a video from king of diy where his arowana had dried up slimecoat which was black in colour

Update!

The black stain was gone! Fish already settle in his new tank! Maybe it his way to adapt in a new tank and new water! Thank you for replying to my thread!