Wattage isn't the problem, it's the spectrum. Best for plants is between
about 5000k and 7000k. With 150w @ 10000k you will, however, grow
exceptionally lush algae.

Ok, if You say so... I will buy 5200K NH bulb. What about wattage? Is it ok,
or too much for this tank?
It will be any difficulties if I put 150W instead 70W?

TIA

M.