Got this from the Tenancy website

For most tenancies, the rent cannot be increased within 180 days of the beginning of the tenancy, nor within 180 days of the last rent increase. The landlord must give the tenant at least 60 days’ written notice to increase the rent in addition to a period allowed to correctly serve the notice. There is no limit as to how much a landlord may increase the rent by, as long as the rent is not increased excessively above market rate.

Rent can only be increased for fixed-term tenancies where provision for this is written into the tenancy agreement.

If the rent is excessive, the tenant may apply to the Tenancy Tribunal for a market rent assessment. If the Tribunal finds that the rent is too high, it may order a reduction in the rent. Market rent applications can only be filed for fixed-term tenancies within 3 months of the beginning of the tenancy or 3 months of the date of the last rent review.

Hope this helps...

Legally it must be 60 days written notice of in increase in rent and this can not occur within 6 months of the last increase but can be any amount.

I used to work in property management before maternity leave and we would never increase it by more than $20 at  a time

I want to know that when the landlord has put the rent up, how much has it gone up by per week, and how much notice have you got before it comes into place??

TIA.