Foods Fish Should Avoid

Feed your fish diets specifically formulated for their type and beware of toxins.

Most manufactured fish food contain all of the nutrients your fish should need. The proportions and quantities, however, may not be appropriate for your fish type. There are some ingredients whose levels can be harmful to your fish – and some common household chemicals that can hurt, too. The guide below addresses some of these issues.

Fish diet essentials

The essential nutrients that fish need are listed below. Research the daily quantities of these ingredients that are required by your fish.

  • Protein and amino acids
  • Lipids, including omega-3 and omega-6 unsaturated fatty acids
  • Vitamins —especially A, C and E
  • Choline and minerals

Small floating pellet food for goldfish in tanks, Hartz SKU 4332400591
Wardley® Goldfish Floating Pellets™ - 2.5 oz.
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The skinny on fat

Fat is harmful to many fish, so be sure to check the fat levels before purchasing a diet for your fish.

  • Regular feeding of beef, pork, or even chicken scraps, can cause fat buildup around your fish’s heart.
  • More than 3% fat can be harmful to the liver and reproductive organs of your herbivore.
  • If your fish is a carnivore, however, he can consume up to a 6% concentration of fat.

Water in fish food

The water content in some dry fish food ranges from 5-15%. If the water content is higher, the food begins to deteriorate. Dry fish flakes can absorb moisture from the air which causes bacterial action. This will break down the food and eventually convert it from a flake to a moist dust. To avoid this problem, try the following:
Wardley® Tropical Fish Flake Food - 3 oz
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  • Always store dry foods in tightly sealed containers.
  • Avoid purchasing a large tin which may be more economical, but could disintegrate before it is fed to the fish.

Live feed

Fish love to hunt for food. If you are going to feed your fish live feed, make sure you observe the following:

    • Food should be clean and healthy. You do not want to introduce disease into your tank.
    • Allow your fish no more than five minutes to eat the food. After that, all uneaten fish food should be removed immediately from aquariums to prevent rotting and water clouding.

hartz_oinkies_tender_treats_small-dogs_1300x1300
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Fish poisoning

If you find several fish dead in your tank at the same time, the reason may be poisoning. Insecticide fumes, paint fumes, cleaning products, tobacco smoke and even cooking oils are common household poisons that are harmful if they get into your fish tanks. When you reach into your aquariums, chemical residues on your skin can dissolve in the water and poison your fish.

Proper nutritional balance and being mindful of what you put in and remove from your fish tanks are crucial in maintaining good fish health.