Welcome to APC!
I suggest that you do two things: First, start dosing per https://www.aquaticplantcentral.com/f...ing-guide.html
, which will ensure that you won't have any deficiencies, so you can concentrate on CO2 instead.
Second: Buy a drop checker, fill the bulb of it with standard 4 dKH water (distilled water with just enough baking soda in it to get a 4 dKH carbonate hardness) and add about 3 drops of API pH test kit reagent. Put that in the tank with the opening facing down, and let it sit for a couple of hours for the CO2 concentration in the drop checker to be the same as in the tank water. Now, adjust the CO2 bubble rate a tiny bit at a time, until the drop checker water color is a light green color. Every day check that color 2-3 hours after the CO2 comes on, to be sure you are keeping the CO2 level high enough. (About 30+ ppm of CO2)
An alternative to a drop checker is to take a sample of the water in the tank, let it sit in the open air for several hours, and check the pH of that water. The tank water pH, after the CO2 has been on for an hour or more, should be about 1.0 lower than that of the water sample. The ppm of CO2 is about 3 times 10 raised to the drop in pH power. So, if the drop in pH is 1.1, you have about 40 ppm. If it is 0.9, you have about 25 ppm.
The plants should then grow very well, and later, if you want to, you can try to see if you have any nutrient deficiencies. Or, you can just enjoy the growth you have, and concentrate on maintaining the cleanliness of the tank, and pruning at the right times.