Long time fish cycle believer
Just a noob here, but I am a long time user of the fish cycle. I tried fishless with plants the last time around and am now a firm believer. If your GF is concerned about ammonia around the kids, I would urge you to consider diluting it before you bring it home. That may help dispel her concern. Just make sure you get the right stuff. Give it a shake and look for bubbles. There should be none. Local hardware store is your best bet.The ammonia gives your plants a huge kick start. I still don't use ferts in that tank, and it has been cycled for a couple months.