Male rainbowfish harassing female

[Rusty_S]

I've just noticed that my male dwarf neon rainbowfish is chasing the female around, he's never done this before but he seems to be doing it a lot tonight. Is he trying to instigate breeding or is this simply normal behaviour? What can I do, should I seperate them?

 

[luxum]

Rainbowfish are a schooling fish best kept in larger numbers, with a larger population of females than males. If you have room, consider adding at least one more female of the same species to prevent any one female from being constantly harassed. A 2 to 1 ratio seems to work well ime.

 

[Rusty_S]

Great thanks, I'll get to the lfs asap to get another one

 

[luxum]

Just be careful, that tank looks pretty well full anyway. A shark in a 21 UK?

 

[Rusty_S]

The rainbow sharks aren't the larger type of sharks you can get for aquaria, they get to be about 4-5 inches, I've kept them ever since I started (about 5-6 years ago) and IME I've never seen them get bigger than this

EDIT: In fact I'm not even sure how old mine is, I think he's been in there ever since I started the tank!