What’s the best substrate for Goldfish?

There is a big debate among Goldfish keepers: bare bottom or gravel? Although most aquarium shops recommend you get gravel as a substrate for your Goldfish tank, some people think it might be dangerous for your fish.

Some of the arguments against gravel:

-When food particles gets stuck in the gravel and rot, they create a toxic substance known as hydrogen sulfite. Pockets of gas can form within the gravel and that gas can be poisonous to your fish. When they forage or you move things around, this gas can be released and it can kill your fish.

-The fish can get gravel caught in their mouths, or ingest it and get obstructed. If you catch it, you can get it out safely, however, there are times when it’s impossible to get the gravel out, or you don’t notice that it actually happened, and then you lose the fish.

-A lot of waste gets caught in the gravel, and cleaning the tank is more complicated. You have to vacuum the gravel very often and make huge water changes (which you always have to do with Goldfish anyway).

Arguments for gravel:

Goldfsih tank with gravel-Makes the tank look a lot nicer.

-It’s necessary if you want to have real plants.

-It also harbors good bacteria.

-Your fish will be happier, since they like foraging. It can also be disorienting for the fish to see their reflection and the reflection of the lights on the bottom.

-Barebottom tanks leave a lot more glass or acrylic surface that can get covered with algae.

Arguments for bare bottom tanks:

Bare bottom Goldfish tank-Fish have a lot more space.

-It’s easier to clean the tank. (Use a window scrubber to clean the bottom)

-No risk of gas pockets or gravel stuck in the fishes’ mouths.

To have a barebottom tank you need to like the minimalist, clean look. You can still decorate your tank, though. You can use potted plants, rocks, decorations, driftwood, etc. Barebottom lovers swear by them and would never go back to gravel.

All in all, using a substrate is mostly for decorative reasons and it really depends on your personal taste. If you like the look of a gravel decorated tank, you might want to keep the gravel at a minimum, no more than one inch, less if possible. You can also use larger river rocks, but the point is to have it be a very thin layer to avoid getting too much food and waste stuck in there forming bad bacteria. Just think what you would be best for your fish.

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