Sunwit is a professional manufacture of fish feed machine, this article is mainly about homemade fish food. The production of commercial pelleted fish feeds is a complicated process. Making a comparably complete, stable product at home is well-nigh impossible.
However, if your fish receive a fair amount of live or naturally occurring food (as is almost always the case in outdoor ponds at moderate population densities), you can make a useful supplemental feed. The available processing technology, however, may be either too small scale and tedious or too large scale and expensive for your needs.
To make very small amounts of feed, you can do as we did at the New Alchemy Institute for our feeding trials: Mix your ingredients with a hand grinder or a blender until you achieve a fairly stiff paste. Next, adapt a caulking gun to squirt this material out in a bead of the appropriate diameter (devices used in fancy pastry preparation should also work). Bake the resulting toothpaste-like material in an oven until it hardens, then chop or break it into pellets.
For production on a larger scale, you can use a commercial chopper to mix your ingredients into a sort of "spaghetti" of the diameter you desire. This feed, when frozen· and shaken in a bag, should break up into pellet-size pieces.
You'll find that a mix which includes some meat or fish will hold together better than a vegetarian formula. However, if you'd rather not use fish or meat, there are food binders you can add to the meal. Old-fashioned commercial feeds contained sawdust, gypsum, or white cheese for this purpose, while modern preparations may include algin (a kelp extract) or gelatin.