水草情迷

I've heard the name TMG (Tropica Master Grow) many times here and I beleive that it's a good fertiliser for aqua plants . I've bought one from the "Water Grass Shop" but I don't know the elements inside the TMG becuase it's a refill type.

Even though I search it from the official website (http://www.tropica.com/article.asp?type ... tic&id=134), there is nothing about the content of TMG as well . Finally, I find the following from http://www.thekrib.com/Plants/Fertilize ... ert.html#0 and I hope it may be useful.

TMG contents
K 0.79%, Mg 0.39%, S 1.01%, B 0.004%, Cu 0.006%, Fe 0.07%, Mn 0.04%, Mo 0.002% Zn 0.002%.

Are these elements same to the "trace elements"?
If yes, do we have to use a few types of fertilisers at the same time? Many thx!