Lobelia cardinalis?

[Goldfish loach boy]

Ok, so today I purchased one of these lobelia cardinalis, or cardinal plant from petsmart, any tips?

 

[Old Scales]

Put a root tab close to them. Don't cut the roots too short as this plant is very buoyant. It is kinda slow to root and will really change leaf shape a lot going from emmersed to submersed growth. OS.

 

[Goldfish loach boy]

Oh ok, thanks! Will be adding a root tab
So it won't look like this forever?

 

[Goldfish loach boy]

Ok, so my plants got uprooted, I was sick and didn't plant them right, but I noticed something, I only see roots in one of them, the rest, it's like they are really tangled in the plant or don't have any, should I still plant them, or what do I do?

 

[Old Scales]

I bought two awhile back. One lost it's roots(??just melted off while in the substrate) It floated and eventually died. The other stayed rooted and lived. It was weird and I don't know why. OS.