Stagnant Plants

[Henrico Coltri]

Hi guys. 
I'm a big fan of the co-op from Brazil and would like some help.
I'm having problems with my plants growth, and i don't have easy options for fertilization or light.
My plants seem stagnant, they don't die, but they aren't thriving.
I don't have access to a fluval 3.0 or something like that, they are not sold here.
The plant specific lights are really expensive and i can't afford them.

So, this is my ~20g planted tank, picture was taken October 28:

At the time of these pictures the tank was inhabitated, but now I added 5 albino corydoras (pics from today):

I have tried to add more hardness to my water with calcium and magnesium carbonate but that didn't help with plant growth (that's the white dust all over everything).

I use a popular substrate from a brazilian company by recommendation of other fish-keepers that have had success with it, which has these specifications:
Formula:

TiO................................ 0,05%

K.....................................0,24%

Ca................................. 1,05%

Mg............................... ..0,84%

Fe................................. .0,27%

Al................................. ..1,16%

Si.................................. .6,35%

N.................................. ..0,40%

P................................... .0,07%

S.................................. ..0,34%

Na............................ ..0,0009%

PPM:

Mn....................................166,

9Zn....................................292,5

Cu......................................14,2

B........................................63,8

electric conductivity 1.600 (umnhos)CTC...................15,5(me/100g)

humidity.............................10%

 

My light is a 50w led reflector like this:

 

These are my tests results from last week (i use SERA tests):
PH= 7.5
GH= 3 drops
KG= 2 drops
nitrate= 10ppm

Temp: ~80º F
 
I don't have CO2.
I have these fertilizers at hand, but they don't seem to do anything (even dosing 2 times the recommended amount.):

Each dose adds the following:

NPK: 
6.0 PPM NO3
1.0 PPM PO4
3.8 PPM K
0.6 PPM Mg

Micro:
0.07 PPM FE
0.01 PPM B
0.06 PPM MG
0.05 PPM MN
0.01 PPM ZN
0.01 PPM CU

Potassium:
2.5 PPM K

Iron:
0.4 PPM FE

Any idea of what i'm doing wrong? 

Thanks in advance.

Sorry about all the information.

[Casual aquatics]

So I was gonna say you need to add some fish fish will create Waste which creates fertilizer and CO2 however corey will eat some plants so you got to take that into consideration if you don’t have access to like super good lights then use what you have to your advantage to put the tank by a window that’s going to get natural sunlight

[Tanked]

Hi Henrico, 

I share your pain. I may be making a very similar post soon.   The Jungle Val I planted 2 years ago put out a few runners and died.  The plantlets are still alive, but they are still 4mm, (3/8th") tall.   My best suggestion is also: add more fish.

I use DIY lights by choice.  I have been using 2ea. 1000 lumen 13 watt 4000K shop lights similar to yours.  My lights measure 4x5x1" and sit on top of the aquarium.  Three weeks ago I added one  840 lumen, 8 watt 5000K Daylight standard LED light bulb.  (65 watt)

The JV have begun showing improvement, with the plant closest to the new light growing a little taller.  The 5000k Daylight bulb might be part of the answer.  You might also try lowering your lights closer to the aquarium.

Good luck