I was so fascinated with this article on fish fertilizer that I asked and received permission from Bill to share this with our readers.
How A Fish Becomes Fertilizer
Reprinted with permission from Bill Ginn
Alaska Fish Fertilizer
Fish emulsion comes from a number of sources, but a sizable majority (and 100% of Alaska Fish Fertilizer) comes from one of two sources- the fish meal trade or the fish canning industry. But as catching and canning of all fish moves off of US lands, and into Asian countries and onto shipboard canneries, more and more of the fish emulsion comes from the domestic fishmeal industry, which is dominated by Zapata Haynie (which, BTW, was founded by ex-president George Bush, sr.)
In the Atlantic Ocean and the Caribbean, there is a small, approximately 8 inch long fish called the menhaden. The menhaden has absolutely no edible value (it is oily, bony, and has very little edible meat) These fish are caught exclusively for their protein values.
Once caught and brought back to shore, they are dumped onto a long conveyer belt, which takes the fish through an oven, where the fish is cooked at 210 degrees F. Then the fish go into a screw press, where the liquids and oils are pressed out. The solids go on to be processed into fish meal, animal feed, and other industrial products.
The liquid is more valuable than petroleum, with pure fish oil selling for more than twice the price of crude oil. The liquid, called stickwater, is placed in a centrifuge, where the oil is skimmed off, and the heavier components, the fish solubles, are boiled down to a thicker, gummier solution that is sold as fish emulsion. A small amount- less than 0.1% by weight- of phosphoric acid is added to drop the pH of the solubles to 4.5 or below. Without this phosphoric acid, the enzymes in the fish would cause it to decay, create gases, and begin to smell horrid- and, all the states realize this, and within certain guidelines, it is still considered 100% Natural Organic (more later on those guidelines). It is then sold on the open commodities market (just like Orange Juice Concentrate, Pork Bellies, or Barrels of Crude Oil), to animal food companies, which use it as flavoring for dog and cat food, additional protein for animal crops (such as cattle), etc. and to companies like Alaska Fish Fertilizer, which have very high quality standards as to which solubles they use for their emulsions (it must be between 49% and 52% solids, have a certain protein value, which I believe is 45%, and other requirements.)
Currently, Zapata Haynie can manufacture about 20 rail cars per day of fish solubles (one rail car is approximately. 20,000 gallons). We accept about 20 rail cars per year- and we are unable to get rail car #21 that meets our standards. Companies such as Ralston Purina take the rest.
After we receive the rail car of solubles at our plant in Renton, WA., we pump the solubles into a tank, where it is stirred, and we make sure that the pH is 4.5 or below. On occasion, we add some phosphoric acid to assure that it is below that pH level. We also add a masking/deodorizing agent at this point. Then it is pumped into our filler (the same kind as is used by Pepsi-Co. and Coca-Cola, but MUCH smaller) and is bottled by volume and weight. Then it is boxed, and eventually it is shipped to the retailer for your use.
And that is how a fish becomes a fertilizer.
And to answer a couple of questions that usually crop up:
Q: Do you get any of your fish from Alaska?
A: No, we do not get our fish from Alaska any more. When we started over 50 years ago, we did, but because of the movement of the Alaskan Fisheries into the far north, the shipping costs have become price prohibitive (about 5 times higher than getting from the east coast to Seattle). Also, salmon remains have a *VERY* strong odor, which is very difficult to mask. However, we think that at least some of the fish that we get from the canneries did spend some time in Alaska waters.
Q: If you add some chemicals, how can you call yourself Natural Organic?
A: Because of the unique properties of Fish Emulsion, the states- who handle the certification of both fertilizers and organic farming- have decided that if less than 1% by weight of fish emulsion is synthetic, then it can pass muster as Natural Organic (the proper term for non-chemical fertilizers). Without this additive, the emulsion creates fermented gases, which can cause rupturing or exploding (with glass bottles like we once used) bottles on the store shelves, or on your workshop bench.
Q: Alaska Fish Fertilizer is more expensive than this other fish fertilizer. Why?
A: There are 3 different types of fish fertilizer on the market- Natural Organic fish emulsion, amended fish emulsion, and enzymatic fish fertilizer. I've already described how natural organic fish emulsion is manufactured. Amended fish emulsion is produced the same way, but it has more than 1% synthetic materials, usually urea, added. A good example of this is Atlas Fish Fertilizer, sold only in California (and manufactured by Alaska Fish Fertilizer), or the K-Gro brand sold at K-Mart. Enzymatic fish fertilizer usually has a NPK of somewhere around 2-5-3 (vs. 5-1-1 or 5-2-2 for fish emulsions), which is a good way to tell which means of manufacturing was used. The enzymatic method has fish scraps being placed in a stainless steel vat, and enzymes are added to cause it to deteriorate. Then the remaining stickwater has the oil skimmed off, and is boiled down to a 40-50% solid solution. At this point the NPK is about 2-0.5-1.5. Then phosphoric acid is added to kill the enzymes that were added (and the pH needs to be lower than 4 for this to happen), then some potash is added to raise the pH level to about 4.5.
The amended fish emulsion is less expensive because any fish solubles can be used, which are less expensive than the higher quality ones required for Alaska Fish Fertilizer. Enzymatic fish fertilizer is very inexpensive to manufacture, has very low shipping costs (since it is usually bottled where it was manufactured), and uses chemical enhancements to raise the NPK.