Wow, such a great idea to be able to choose what goes into the food for your fish! RDTigger - how did that recipe turn out?
I found one which uses baby food, which sounds more manageable for those with a smaller fish load. It's a vegetarian recipe, but I'm hoping to add ground up shrimp to the mix, along with some spirulina.
http://www.wetwebmedia.com/ca/volume_6/volume_6_2/food.htm
To make this recipe, you’ll need a microwave, a microwave safe measuring cup, a small spoon, and a mold in which to put your gel food. I use a 32-ounce (one-liter) yogurt container cut in half, but an ice cube tray or a disposable plastic cup would work equally well.
Yield
About 1 cup (~8 oz/0.25 liter).
Ingredients
a 4 oz jar of vegetable flavored baby food **
a 0.25 oz (7 g) packet of Knox unflavored gelatin
4 oz (1/2 cup) of drinking water
** (I prefer the Beech Nut brand because it is preservative and additive free, but Gerber Simple is another such brand. Beech Nut flavors I recommend are: Tender Golden Sweet Potatoes, Tender Sweet Carrots, Tender Sweet Peas, Tender Young Green Beans, Butternut Squash, Carrots & Peas, Corn & Sweet Potatoes, and Country Garden Vegetables. Fruit flavored baby foods can be used also, but sparingly, due to the higher sugar content.)
Method
1) Pour 4 oz (1/2 cup) of drinking water into a microwave safe cup.
2) Microwave for about 3 minutes, or until the water is boiling vigorously (a rolling boil).
3) Dissolve 1 packet of gelatin in boiling water. Stir, smoothing out as many lumps as possible.
4) Pour 4 oz of baby food into the cup of gelatin-water mix. Stir evenly, removing any lumps that float to the surface.
5) When mixture has thoroughly blended, pour into mold. Let it sit in the refrigerator for at least 2 hours.
6) Transfer gelled mixture from mold onto a plate or cutting board. Cut into the pieces suitable for the size of your fish.
7) At this point, you can store a portion in the refrigerator for ease of serving, and freeze the rest. I recommend estimating how much your fish will eat in a week, and keeping that much in the refrigerator. Store in an airtight Ziploc bag or Tupperware container. After about a week, discard uneaten gel food from the refrigerator. Frozen gel food will keep for approximately one month; longer than that and the gel food begins to show signs of freezer burn.