Ottos changed their behaviour

[Country joe]

When I had my Ottos in my 125 litre, I never saw them, they were in a tank with peaceful fish mainly Tetras, in fact I never saw them for a month I thought they had died.
Now I've moved all fish to a 200 litre tank the Ottos are out every day in full view they are in the new tank with the same fish, same type of gravel, I wonder why they have changed their behaviour.

 

[MaloK]

If your tank has recently been setup.

Food availability has reduced and they are pushed out to find it.