This seaweed is a bit of a worry

[Lilith7]

Probably will end up introducing another fish species that eats it if it becomes a major issue.

Dabbling with ecosystems in that way is more likely to result in downstream problems such as the reduced snapper population has contributed to (caused) the likes of kina barrens.

Everything will have advantages & disadvantages, even were we to check everything as carefully as possible there might still be things we weren't aware of to cause future problems.
There was a time whan plastic was thought to be a wonderful thing because we didn't know what was ahead..