How much can I raise the rent on a 10 year+ renter at just $600.?

[Kenneth Davis]

I have a tenant who I have rented to for over 10 years at $620.00 monthly who I have never raised the rent on. I wish to raise the rents here in Florida on this guy but not sure if there are restrictions on raising his rent. I wish to raise the rent by $50.00 monthly which would greatly help me with all the services I pay for to manage this rental. Is $50.00 asking too much? My rental is $200.00 below market for 2 bedroom 1 bath for the Jacksonville area it seems.