Well what Klaus sold you is cured live rock and your tank will go through a quicker cycle than without it. Still as Matt said buy or have Klaus do a water test for ammonia, nitrite, ph and alk. Should be zero, zero, 8.2 ish and about 7-9 meql. You mention plants but I am not sure what you have as most plants don't live in saltwater, could this be macro algae or do you have some coral in there? You need to leave the lights on for up to 8 hours a day as you are simulating coral reef conditions with light up to 12 hours a day. It is normal to go through many algae cycles, the one you are currently going through is probably just diatoms perfectly normal. Some turbo or astrea snails will help take care of it. You must make sure you have mixed water available for water changes and emergencies especially with a relatively new tank.....keep on hand enough to do 50% change in a hurry if needed. Get some ro/di water from Klaus or if in a pinch you can buy water from Meijer water dispensers....I used that water for a couple years before I bought my ro system. Mix the water with your salt mix (about 1/2 c per gallon) to a sg of about 1.025. areate it and heat it and test the ph to match the display once they match.....swap out a bucket full (3 gallons) You should do this once a week if not using a protein skimmer......good luck....sounds like you are on your way.