Sometimes there are certain situations where a direct teaching approach is not possible. I found this out with newborns and fish. Firstly I am unsure if they are capable and secondly there is no direct feedback to tell you if they received the message. You then use the trial and error method: Try something and see if you receive a satisfactory result. Small goldfish are very skittish. This is reasonable because they are so small and have been largely mistreated. Here is how to teach them to eat vegetables.
Small 1.5 in goldfish eating vegetables. They are skittish at best but will eventually eat. Keep the leaf in the tank for up to two days. Photo by Don Tai
Eating is one thing that all living beings need not be taught. Ditto for breathing. Still it took over 24 hrs for my young and small goldfish to realize that the green leaf flapping in the current was edible. Once they realized the green object was food, they ate it off quickly. Initially they would not go near the leaf, which is as large as their bodies. They then began to touch it and then run away. After a couple of hours they began trying to nibble at it. Then in the morning the leaf was bare. I have read that vegetables are excellent for goldfish, and that feeding them only goldfish pellets or flakes is not sufficient for their diet. Note that once they recognize that the leaf is edible, small goldfish need to learn how to eat. They will pick at all parts of the leaf, including the middle, until they learn that a leaf is best eaten from the edges on inward. I suppose this is readily apparent to us, but to small goldfish this is a learned skill.
Small 1.5 in goldfish eating vegetables. Leaf hooked to a suction cup using a small wire. Photo by Don Tai
We had Chinese bokchoi 中国白菜 in the fridge. I prepared the leaf by putting it in a bowl of water and microwaving it for 45 seconds. This softened it up quite a lot. I then used a suction cup and a twist tie (small wire), put the twist tie right through the stem of the leaf, and pushed the leaf and suction cup down to the bottom of the tank. Goldfish most often swim at mid to low levels of the tank, so if you put it up high they might not see it. Leave the leaf in the tank for up to 48 hrs, after which it should be removed because it will start to rot. Be patient and they will eat, which they do so well. I find my little fish wait about 12 hours before they start eating, maybe to wait for the leaf to further degrade and soften up. They eventually eat everything except the thicker veins of the leaf.
You can buy a food clip that comes with a suction cup from the local aquarium store, but my suction cup and wire does the trick. You can also make your own food clip. Recently I found a plastic clothes clip that had a hole in the handle. I enlarged this hole and inserted the nub end of a suction cup. This clip also works well, though you need to dip your hand into the water to attach the leaf to the clip. The clothes clip grips the leaf more securely than the wire.
Small 1.5 in goldfish learning to eat vegetables, 24 hrs later the leaf is well eaten. Photo by Don Tai
