Trim often. For some plants, I had to cut and replant the top part quite often. Basically it is a small underwater garden you have to deal with.
Keep the lights on for no more than 10 hours a day. Some people keep it on for only 8 hours or less a day with a break of 1 hour in between. Use an automatic timer to turn on/off the lights will save you a lot of trouble.
With eco-complete, your plants won't run out of iron for years to come. There is no need to add any more iron. For other minerals, eco-complete can still offer plenty of them for at least a year or so. Don't take my word on it, but that is the general accepted idea on the net for eco-complete based planted aquariums.
You do not have to get CO2 from the beginning. Just give some time and see how it goes. A lot of plants can do fine without it.
Another tip is, you can put your air pump on timer. During the time when the lights are on, the plants will produce O2. You do not need a lot of surface movement for gas exchange at this point. At night, it is quite the opposite since the plants actually produce CO2 in the dark. Your fish will need extra O2 from the gas exchange. Yeah, two automatic timers are needed for this to work. Basically, the air pump gets turned on at the same time the lights are turned off. <--- That was my own personal idea. You do not have to follow lol.