Schooling fish

Right now there are platies, serpae tetras and cories. I want to get rid of the serpae though as they are harrasing my platies.
 
harlequin rasboras. i just got a school of 15 for my tank. they school pretty well... usually a main group of 10 or so moves as one, then there'll be a few stragglers all over the place. very cool fish, awesome colors, nice and peaceful. occasionally my yo-yo loaches will swim right into the middle of the school and they go every which way, but other than that all is well. plus i think they're more active than some of the smaller tetras. i remember neons just kind of "hanging out", whereas these guys are always on the move. highly reccommended :)
 
Well I was going to take the 4 Serpae back but now I'm not so sure - they seem to have calmed down a bit with the harrassing.

However, what I have noticed is that this fish (I only have 4) is a very nice schooler. They swim back and forth in a group and they are very nice to watch. So I'm not sure if I should keep them or not?
 
AquaDummy:

I posted an answer to your problem in another post. But larger tetras need more space and more of their own kind. With a good school (6 or more) in a big tank they are not aggressive. This may not be the rule but just my experience.
 
I've got a good size tank but I ended up netting them out anyway. Basically I had to take my tank apart to get them but I did it. Now I just hope I didn't stress my other fish to the point of losing some of them..
 
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