Bichir activity level

Many know that Ive been contemplating some changes in my 72g bowfront due to a lack of interest in my bichirs or should I say a lack of interesting activity from my bichir. Overall they are cool but they are not a wet pet that interacts with you. They are pretty much just tank decor.   

So out of my different ones my del and albino sen are active enough that I would consider keeping them. The 'gold dust' is going to be sold.

Here is the one I have questions on, the weeksii. This one is super shy and I can not get it pellet trained. It was a wild caught specimen so that might be one issue. It is also still small at about 9" and has external gills still.

Will I see any improvement in activity when its older?

Is it shy because its still a juvenile?

Any ideas or help appreciated.

I posted on MFK also to see what others say about this.