All that toxic sewage being sent up to us from Mexico.
“All that toxic sewage being sent up to us from Mexico.”
Untreated sewage is dwarfed by the amounts of nitrate and phosphate fertilizers that wash down from Central Valley irrigation districts outflows. Those two nutrients are almost always the cause of red tides. Every year so much of them wash down the Mississippi River that a huge dead zone forms in the Gulf of America hundreds of square miles in area as the algae blooms die and sink to the lower waters where they rapidly consume all the available O2 causing a huge anoxic zone to form.
There have been ideas to take huge fish pens some a full kilometer in diameter to the blooms on the Gulf’s surface with filter feeding fish like menhaden or mackerel in huge schools of them. Let the fish chow down and fatten them up while cleaning the water of the blooms. Then either grind the fish up to fish meal which is high protein feed like 60% pure protein , plus fish oil and solubles. Or take the fish press the oil out , take the filets off and the bones are nearly pure calcium phosphate perfect for fertilizer that also doesn’t tend to run off as the calcium locks it into slow release for roots. The other choice would be bivalve in floating sacks or ropes to filter feed all the algae out yielding again protein and shell mass , shells are calcium carbonate so a feed ingredient for cement or concrete.