You can connect as many accounts as your plan allows: live, demo, challenges and funded. Each one needs its own key and its own EA on a chart in that terminal.
An active key takes one slot. If you revoke a key the slot frees immediately and you can use it for another account. The history you already uploaded is not deleted when you revoke.
If you need more accounts than your plan includes, you can buy extra accounts as an add-on in My account, without changing plan.
On the dashboard you can see the combined portfolio or go account by account. The comparison screen is useful to see whether you really trade the same on demo as on live — the answer is usually no.
Onyx Trading Live