Thai Fisherman

Fish sauce - from Thailand how is it made?

I work casually at a Thai restuarant and have taken a liking to the food. I normally take some home at the end of my shift, but I would rather cook it fresh. My boss has given me the recipe for Tom Yum soup with Noodle for me to make but when my husband saw it had fish sauce in it - a vital ingredient - he refuses to try it.
He has been told that fish sauce is made by fisherman catching fish and leaving them in big nets over drains and the rotting oil from the fish is dripped down the drain and collected to make the sauce.
Is this true? and if it is, can I substitute soy sauce instead of fish sauce in the recipe so my husband will eat it. I don't want to offend my boss by asking her due to the language barrier.
Thank-you

Here's an excerpt that tells how it's made. You can click on the link to read the full article. The nice thing about this article is that it's authentic, written by a Thai author about Thai fish sauce.

********** ********** ********** ********** **********

How Fish Sauce is Made
Made From Fresh Fish From the Sea Fish Sauce Does Wonders for Thai Food

by Kasma Loha-unchit
Copyright © 1998 Kasma Loha-unchit

http://www.thaifoodandtravel.com/features/fishsauce1.html

"For fish sauce to develop a pleasant, fragrant aroma and taste, the fish must be very fresh. As soon as fishing boats return with their catch, the fish are rinsed and drained, then mixed with sea salt – two to three parts fish to one part salt by weight. They are then filled into large earthenware jars, lined on the bottom with a layer of salt, and topped with a layer of salt. A woven bamboo mat is placed over the fish and weighted down with heavy rocks to keep the fish from floating when water inside them are extracted out by the salt and fermentation process.

The jars are covered and left in a sunny location for nine months to a year. From time to time, they are uncovered to air out and to let the fish be exposed to direct, hot sunshine, which helps "digest" the fish and turn them into fluid. The periodic "sunning" produces a fish sauce of superior quality, giving it a fragrant aroma and a clear, reddish brown color.

After enough months have passed, the liquid is removed from the jars, preferably through a spigot on the bottom of the jars, so that it passes through the layers of fish remains; or by siphoning. Any sediments are strained out with a clean cloth. The filtered fish sauce is filled into other clean jars and allowed to air out in the sun for a couple of weeks to dissipate the strong fish odors. It is then ready for bottling. The finished product is 100-percent, top-grade, genuine fish sauce."