I'm in the process of getting things ready for my 55G planted tank and I'm
gonna be doing a big order from BigAl's very soon, so I'm looking for
feedback about which plant food/supplement would be best to order. I know
that the best way is probably trial and error by seeing what your plants are
lacking, etc. but I'm looking for recommendations on where to start, since I
really would like to order everything together (since it's cheaper that
way).

This is what I was thinking. I'm not up to any CO2 injection, so I thought
of using Flourish Excel to help out with the carbon. Would dosing this if
my plants don't need it cause any problems (ie: algae)? I was also thinking
of maybe ordering Flourish. Is that a good idea? Is it pretty common to
use the "all in one" Flourish supplement, or is it more common to find out
exactly which elements the plants need and use the separate bottles? Btw,
I'm located in Toronto, ON, Canada, in case anyone knows what the water here
is usually lacking.

If you were in my situation, what would you order before knowing exactly
what your plants will react to? I know it would be best to wait, but I can
save if I order everything right now.

Thanks,
Harry