updates on my 125 with pics:D

Diftwood is allways nice and I would get rid of that plastic container

you could use CO2 if you want better plant conditions. they all look healthy to me

A plastic container with plants would look weird with the rest of the tank bare. You should really consider some substrate If you like plants

If you want to get rid of the plastic containers but still keep the bare bottom for most of the tank, why not look for some glass containers to put your plants in? You can find square and rectangular ones commonly used for floral arrangements in most arts & crafts stores.

Here are some examples:




However, neither the plastic or glass containers allow water to enter the substrate from anywhere other than the top. I don't know enough about aquarium plants to say if this is a bad thing or not. Maybe ask around.
http://www.save-on-crafts.com/squarevase4.html

you will have problems with your pleco in the tank, remove it and get a uvster-

Could use root tabs as far as the plants go if you are worried about them getting the essential nutrients.