Is It A Aquarium Plant

[Discuslove]

I bought a few different plants from a LFS but this one particular plant isn't growing well at all, I fertilise the plants everynight with seachem flourish and liquid CO2. This plant was labelled as low lighting and same as all the other plants i have gotten. All the other plants are growing well and have had their first trimming besides a couple which are really slow growing. I went to a shop today and was in the gardening section and saw a plant which looked very similar. I went home and looked up the name of the plant that was on the label when i bought the plant, it was labelled as a "Yellow alt". I found nothing on it. 
 
So here is a picture of the plant. It is a bit hard to see and has not improved at all, no new growth and has only gone downhill.
Do you think it might be a non-aquarium plant??
View attachment 71196

 

[frapadoodle]

When in doubt, yank it out. Many shops sell non aquatic plants.
I see Acorus and Mondo grass everywhere, neither of which are aquatic.
As to ferts, why everynight? I use Flourish twice a week, and my plants are going ape.

 

[Discuslove]

I only have filter sand and very low lighting and so my plants need the constant ferts but i may get some root tabs.

 

[frapadoodle]

I only have playsand and low lights.
My swords throw out a leaf a week.
But tabs wouldn't hurt.