Depending on which type of aquarium fish species, some of the baby fish can be as tiny as few millimeters in which you will need the magnifying glass in order to see them clearly. Most of these tiny fish fry are those which come from the cold water and tropical egg-laying fish species such as goldfish, koi, neon tetra, and pencilfish. Yes, don’t be deceived by the large gigantic koi size because you will be surprised to see the young baby hatchlings can be as little as 3mm in length. However, when it comes to the live bearers which release free swimming babies, their offspring are much larger in comparison. You might want to find more information about fish and koi breeding methods here.

Another option which you can use is the cheap microworms. I would definitely recommend using these for those growing live bearer baby pet fish and for those small hatchlings like the baby goldfish, I would suggest you feed them infusorians for at least 2 weeks before you use microworms. I’ve written a comprehensive guide on how to get cheap and continuous supply of microworms just by regrowing the culture and making sure that they regenerate back the numbers. Apart from using microworms or infusorians, you can also mix in some dried fish pellets to add some variety to the diet by soaking the pellets in a small container until you can crush it until it turned powdery.

Finally if you are staying close to areas with ponds and stream, that would be even better because you will have the chance to collect daphnia which thrive in green water. For further information, refer to choice of other live aquarium fish foods. You might also want to find out about different types of fish species.