This is what I would do, water change every second day for the first 2 weeks, after this once a week, low light, max 5 hours a day for the first month, could go up to 6-7hrs after a month of decent growth, you want your co2 to drop the ph by 1 point before the lights come on, generally needs to start co2 about 2 hours before lights on, can probably switch co2 of a hr or more before lights out, ferts from day 1 probably at half EI levels looking at your plant mass, perhaps even less, PH hardness etc dont matter so much, personally i never really measure these, when i do its only to gauge if i am getting 30ppm of co2.