Depending on your income, considering you have a debt to pay you may be asked to provide an Assurance of Support (AoS). If you are earning enough money, the fact that you're paying a debt won't change anything; if however immigration doesn't think you have enough funds to support yourself aswell as your partner they will ask for an AoS.
You cannot organise an AoS until immigration sends a letter asking for one (this will be asked for near the end of the visa process, once eveything else is cleared). You must then find someone, or a group of up to 3 people, who have enough funds to support your partner. They go to centrelink and centrelink assesses their capability to be an AoS. Once the AoS is approved the visa will be granted.