Altum Darting around

[tannc2]

I had 12 Altum in a 4ft planted tank for 3mths already. Everything is doing fine and they had grown from a 20cent size to more than 50 cent now.
I did water change every week but last week, after water change, the Altum starts darting around and hidding behind plants whenever somebody walked pass the tank. They don't normally do that and is always swim out in the open. But after that water change they became so timid and was hidding. Anybody know why? Is it water parameter or illness?
Please advise.... Thanks

[Simon]

They probably got scared during the water change. Don't get overly worried, try planting echinodorous to cushion their dashes.

Are there new additions to your family? avoid having your tank along the routine walk ways in your house, that will reduce stress to the fishes

[tannc2]

Thanks for the reply. Just hope that they will calm down after a while. Yesterday when they are dashing one of them jump out of the tank lucky I am around to pick it up and place it back almost immediately. Hope that nothing is broken.
Just make a head count, every fish is still there.

[blim]

I have 6 altums for nearly 4 mths in a 4 ft tank. I do 10% water change daily in the morning to siphon out the faeces. They will hide behind a driftwood when I do the water change. If I don't disturb the area where they are hiding, then it is OK. But once they are disturbed, then it take a while for them to calm down.

At home, I usually wear white T shirt and they are used to it. If I change into strong color dresses and approach them, they will back off. They stay away go into hiding when other people approach them suddenly. They also become sensitive when there is a contrast of light between the tank and the surround. For example, when the tank's light is on and the surrounding is in darkness at night. Or the tank light is off and the surrounding is very bright with reflected sunlight.

You see, very sensitive fish.