Does It Matter If I Don't Give It Goldfish Food As long It Is Fish Food?
Goldfish being omnivorous, they will eat any fish food offered.
I am assuming you are referring to dry prepared food purchased from a pet shop or supermarket.
Check the expiry date, or, if it has been opened and you have had it for more than 3 months it will be past its best.
Depending on the variety of Goldfish you have, feeding this type of food exclusively could lead to digestive problems.
If your Goldfish is a single tailed variety, they can put up with poor quality food better than the fancy varieties. Ultimately you will
get digestive problems with fancy varieties, often showing as a swim bladder problem where the fish will float like a cork, or sink to the bottom.
Feed some vegetable matter such as kale or spinach with the food to provide roughage.
The best foods for Goldfish are gel foods. I recommend Repashy Soilent Green
as it contains both vegetable and protein matter in an easily digestible form. My fish love it.
It is easily chewed and swallowed as it is moist and I haven't had one swim bladder issue since using it.
Check the protein level of the food you have, it should be around 40% for younger fish. Be careful of what the protein source is as some cheaper foods use chicken feathers!
The food may be good quality if it has been made by one of the big manufactures such as Wardley's, so test your fish on a small amount first. You will soon see from its response if it wants more.
If your fish becomes lethargic or shows buoyancy problems after eating the food, stop using it immediately.