I'm gonna have to start using GPT more lol. I'd say the first point of being expensive and complex applies to any climate change solution so its more a matter of relative complexity and cost. Number 2 makes sense, the used water from the algal bloom would still have to go back to the water treatment system, but it might be easier to clean since it no longer contains nitrates and phosphates. I'm not sure if 3 would matter since we wouldn't have any other aquatic life existing in the bloom. 4 was surprising to me, I didnt know algae could release methane and nitrous oxide, that would definitely have to be avoided.