CO2 advice?

[Delphinus]

I want to add CO2 to my planted freshwater. Mostly anubias right now, some other various plants, and some java fern. Want to go with more eventually. Tank is a 30g, current lighting is 4x20W NO (daylight tubes).

Was thinking about starting with 6-10 bubbles per minute. Is that a reasonable starting point? I don't want to shock the system. What are things to watch out for?

I can measure my pH plus I do also have a CO2 test kit, so I should be able to monitor the levels but I don't know what are good values to use as targets.