Old clowns - new mates?

[KimiS]

Hi all!
I have two Clown loaches who have survived various moves and other upheavals with no problem, and always been very active. They are now 10 years old and 5 -6 inches. They have become very nocturnal hiding under a log, and I rarely see them apart from at dusk or dawn (and with blue moonlight). When I do see them they seem prefectly healthy and happy.
They are in a 4' foot tank with a few boesemani rainbows. If I was to add 2 or 3 more young clowns loaches would that encourage the "old" guys to come out more and be their old clown selves? Or is this an age thing?
I want to start adding some new stock to this tank, so I guess my question really is whether or not to add more Loaches (clowns or other?), or just leave these guys to themselves, and add other compatible fish instead?
Any ideas/opinions would be appreciated!
I should add that the 4' tank is to become a 6' within the next six months!

[Ardillakilla]

My loaches are ~7 years old and all except one are out all the time. I don't have lights on the tank. I also have no dithers, no other fish other than loaches in that tank.

They just don't seem to like light hence the dawn/dusk thing you've noticed.

[KimiS]

So thats good to know about the dawn/dusk thing - thankyou!
Would these "old" clowns be upset if 2 or 3 new young clowns joined them? These guys have been a pair for 10 years now. Or would I be better off getting other compatible fish? Sorry to sound so naive about it all - just want to do whatever is as right as possible! And re stock my tank...!

[Ardillakilla]

If anything, it would encourage them to come out more, especially to compete with the small ones for food. When I added my small clowns to the big ones, the big ones didn't mind them at all but the small ones were wary of the big clowns for a little while.