Need PH/GH/KH and nitrate/phosphate tests. Do you have fish you feed in tank?
Also once a week dump and run dosing is not best way to manage a low tech tank.
Is tank 60 or 80 liter?
Probably around 2ml needed for your tank weekly, maybe 3ml if plant load high enough, especially if you have any floating plants. Divide that by 7 and dose daily or divide by 3.5 and dose every other day.
Problem with once week dosing is plants will have all they need at initial dose, sometimes in excess but then towards end of week the levels, especially of trace elements will bottom out stalling growth. Slow and steady dosing wins the race in low tech tanks. If you can find time to feed your fish everyday you can find a extra 30sec to feed your plants every or every other day.