I screwed up when I changed my substrate a couple of weeks ago. I did not save enough of my bacteria and the tank is re cycling. Ammonia just went to zero a day ago and nitrites are at 0.5. So I am likely two weeks away from finishing my cycle.

After my last plant failure I have changed the substrate, changed my lighting plan, and changed my plant plan. Last time I added a lot of light and injected CO2. I wound up growing lot of algae. This time I want to try the Low Tech approach.

Should I wait the 2-3 weeks for my tank to complete it's cycle, or can I add plants now?

thanks, Mark

You should add plants now. It is fish that you want to protect from the ammonia and nitrites. Plants are an alternative path for nitrogen. Plants and bacteria are competing for the same ammonia. Plants are a higher life form and thus better compete for the ammonia. In fact when the plants take up the ammonia then you end up without any nitrates in you water. If you have enough plants, when you trim and remove them you are doing the equivalent of a water change in a non planted tank, because you are removing nitrates. dig?

I agree. Having plants in a cycling aquarium can make your tank experience a 'silent' cycle where the plants use the excess ammonia and nitrite. It can appear as if your tank is going through a mini cycle, fully cycled, or even stalled thanks to the plant flora. Remove the plants and you will see ammonia and nitrite spike... I learned that the hard way :/