How To Promote Plant Growth?

[AshleyNZ]

I've had my tanks set up for around 6 months, and so far I haven't been able to get lush green growth like many other forum members i've seen. 
My tank is roughly 50 or so gallons, with a pink 4 foot lighting tube, and a white one, each 40 watts, totalling 80 watts, and the tank itself is around 1 1/2 feet deep. 
The substrate is silica sand, and I also added JBL root balls awhile back. I dose around 10mL of flourish biweekly too, but I'm wondering if there's anything else I can do
to make my plants as beautiful as some of yours Any advice/product suggestions welcomed!

 

[Byron]

One suggestion may be the plant species, which are not mentioned.  Different plant species have different requirements when it comes to light and nutrients.  From your data, my tanks seem similar in lighting and fertilization, but there are many plants I cannot even grow, so I have stayed with the ones that do manage.
 
A photo may help, as I or another member might see something we could advise on.
 
One thing about the light though...this is the single most important factor, and it would help if you could provide some data on the specific tubes.  The Kelvin would be worth knowing, this may be printed on one end, or on the packaging if you still have it, or online if you know the manufacturer.  In my experience the "pink" tubes are weak in intensity, so the solution might be as simple as replacing this one tube, or both depending.
 
Byron.

 

[AshleyNZ]

Just an amazon sword, java moss, java fern, anubias nana, ambulia and rotala currently

 

[Arcticfox1977]

Your swords, Javas and Nubia's don't need much attention. These are known as beginner plants. I have them also. I dose ei ferts and carbo, which is like flourish. My plants are green and healthy. I can't comment on the other plants.
Also I have basic lighting that came with the tank.

 

[Byron]

I agree that Java Fern, Anubias and Amazon swords are relatively easy; the otyher two are stem plants which naturally need a bnit more light and nutrients, being much faster growing.  Swords are heavy feeders too, but tend to fare much better than stem plants in moderate lighting.
 
I am still waiting for data on the lighting, as without that it is impossible to offer any suggestions as to what, if anything, is an issue.  And the photo might tell us a lot too, not only signs of problems, but perhaps your plants are really doing well after all.  Sometimes those of us with low-tech or natural method planted tanks see photos of high-tech set-ups and immediately think we're having problems, when we're not.  Plants grow differently, as I mentioned previously, and will respond differently according to their environment.
 
Byron.