I read the article and note two things. First, the problem is largely attributed to temperature, which phoslock cant control. In addition though, the farming appears to be in large nets in ocean waters, much like salmon farming in Tasmania. Phoslock can't do much in open water because it works best on enclosed water systems. I assume the aquaculture systems Prince refers to must have been enclosed ponds? if you used phoslock near the cages (for example) the concentrations would just equalise rather than one little area remaining 'treated'. It theory, you'd almost need to treat the whole ocean (or a massive part), which you clearly can't do. Although it would be a nice order...
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