sea weed

Sea weed
I got some sea weed for the hydro shop for my plant`s.....I`m in the flower cycle now (2 week`s ) I haven`t used the sea weed yet...! do you think I should use it ? .... I have not used it because I have read that sea weed can grow very fast and BIG .....my plant`s are abut 18"in
if I start to use the sea weed will the plant`s get even bigger very fast ?
I know that sea weed haves very many benefits such as increasing metabolic rates and conserves plant energy to help produced MOOR AND BIGGER PLANT`S I `m just a little concern that they will get to big.... and over grow my space
I `m using gh 3 part + kool bloom + floralicus bloom formila + silka all G.H !

The sea weed is Max icrop ( npk 0.1 - 0.0 - 1.0 )
G.H kool bloom ( npk 0-10-10 )
G.H floralicus bloom ( npk 1-1-1 )

I have not used it before but if you follow instructions. I don't think it will make them that big. Sounds like a mild additive. Mostly bennificial organisms.