clownfish and new mate

[al404]

Hi

 

I have a 15G tank that is running since 1 year, at beginning of 2016 i add a clownfish and a blenny

 

I don't how this summer the blenny got in one to the 2 power head while it was off and when it got on it died

 

this sunday i decide to add a new clownfish, after a couple of hours of fight the are not fighting any more the smaller one sometimes get close to the bigger and swim together

 

the older newer swim that much even when it was a small fish, is a true pecula

the new one it swims all over the places, is a false percula

 

are some clownfish swimmers and other just sit in one place?

 

what i noticed and i'm little ware about is that my older clownfish used to sleep in upper right corner and did not wake until light come on, now i'm not even sure that is sleeping during the night

the little one doesn't seem to sleep, and in the morning at least 3 hours before lights goes on are both swimming

 

is that normal?

 

last question

can i add a small fish like blenny or okinawe? if i can should i doit as soon as possible?