Join Date: Mar 2013
Location: Montgomery Village (back to NYC soon!)
HC is a CO2 hog; was the tank you got it from getting pressurized CO2? I am assuming from your post above the current nano is not.
In my experience, when starting a new carpet, there will be some vertical growth as the the plant acclimates, but depending on your lighting, it should mainly spread horizontally across the substrate and you can trim any small shoots that come up over time (although I find my carpets are growing vertically less and less over time).