My girlfriend had an emergency, and I had to take her 4-Line Damsel before it died.
I put it in my 20-tall with a Yellow Tail Damsel and a large Ruby Scat.
The Yellow Tail is just a bit larger than the TINY 4-Line, and has been there for about 6 months while the Scat is like 8X the size of both and has been there for about 2 months. The scat is SUPER calm and leaves everyone alone.
My prob: The Yellow Tail is really picking on the 4-Line, and keeping him up in the corner, even though I've read that Yellow Tails are the least aggressive damsel, while 4-Lines are one of the most aggressive... so I thought it'd work.
Option 1: Take Yellow Tail to LFS... cause I like 4-line better

Option 2: Move 4-Line or Yellow Tail Damsel to 60g where I have...
-Medium Yellow Tang (kinda aggressive now)
-Large 6-Line Wrasse
-2 Paired Ocel. Clowns
-Lawnmower Blenny
-Fire Shrimp
I'm worried the Yellow Tang will kill (killed a small wrasse months ago), or the damsel will pick on my lawnmower... not really worried about much else... 6-Line is pretty chill and keeps to his own, and clowns keep to their anemone.
SUGGESTIONS????