Three male dwarf gouramis together? Or a male and two females?
ONE albino cory? Do you already have some?
The rainbowfish is a shoaling fish (I'm getting deja vu here) so its chasing behaviour may be down to feeling threatened and vulnerable.
...and you added these to your already obscenely overstocked tank in your sig?
What are you planning on putting in the biorb??
1. Dont give me any slate!

2. I do not know the sex of the gourami's. 3. 4x corydoras read my sig. 4. i know

5. Gourami's.
1. Post on a public forum, expect comments. I'm not slating you.
2. How can you not know the sex? Are they colourful or plain silver? Keeping males together is asking for trouble.
3. Are they all albino corys?
4. If you know you're overstocked why have you added MORE fish? Or do you mean you know your rainbow should have company - again, if you know this, why not deal with this?
5. You cannot put those gouramis in the biorb. Simply cannot. Lack of research again.