Fish Bowls

This page contains information and advice about keeping fish in fish bowls. You can read about starting a fish bowl, water that is safe to put in fish bowls, how to clean a fish bowl, where to put a fish bowl, and what fish to put in fish bowls - not goldfish!
How to Start a Fish Bowl. When you choose a fish bowl, pick a big one: at least one-gallon. You’ll also need a small 3" wide fish net, two 1-gallon bottles of drinking water not distilled or de-ionized water, and some floating fish food. Together floating fish food that is labeled for your type of fish plus some freeze dried blood worms, which are actually mosquito larvae, make an excellent diet for the fish in your fish bowl. Don't buy or use fish food that sinks.


1. Water from the Tap Isn't Safe for Fish.
Even if you treat the tap water straight from the faucet with water conditioner it still won't be safe for fish in fish bowls. Bottled drinking water is safe for fish in fish bowls.
Fill the fish bowl 2” from the top with the bottled drinking water, not bottled distilled or de-ionized water, and then cover your fish bowl with a clean plastic cover from a can of coffee so the fish won’t jump out.
Your Fish need fresh water. Your fish can’t live forever in the same old water. Twice a week replace 20% of the water in your fish bowl with bottled drinking water.


2. How to Change Some Water in your Fish Bowl.
Twice a week pour out 20%, not all, of the water from your fish bowl. Be careful not to pour any fish down the drain. Use bottled drinking water to refill your fish bowl. Don’t fill it higher than 2” from the top of the bowl. What to do with the old water? It's very good for plants.
I filled my 1.5 gallon fish bowl about 3" from the top. Then I slowly poured some of the water into a measuring cup, noted how many ounces were in the measuring cup, and continued pouring the water into a measuring cup, until I'd measured all the water, and added up the total. It came to 160 ounces, and 20% of 160 ounces is 32 ounces.
Then I realized that my 1.5 gallon fish bowl had about 1 quart of air at the top plus 5 quarts of water (5 quarts x 32 ounces-per-quart = 160 ounces total) and 20% of 5 quarts of water is 1 quart of water. So in my case it was easy to do the math.
I was just lucky, but if your bowl has 151 ounces of water, or some other unlucky number. You'd still multiply by 20% to find out how much to change each week. In this case 151 x 20% = 151 x 0.20 = 30.2 ounces, rounded down slightly to about 30 ounces.


 3. Making Bottled Water
When you’ve used all the bottled water, you can make more safe water for your fish bowl by filling the empty plastic water bottle with tap water from the faucet.  Leave 2” of empty space at the top of the bottle.Add five drops of water conditioner, put the cap back on the bottle tightly, give the bottle a good shake to mix the ingredients, and then let the bottle sit for three days before adding the water to your fish bowl. Click here for more about water conditioner.

  4. How to Clean your Fish Bowl.
After a few weeks algae and other stuff will start to coat the inside of your fish bowl. It won’t hurt the fish, but it doesn't look good, and you should get rid of it. Here’s how; pour 80% of the water from your fish bowl into a clean bucket, then use your 3” net to carefully move all the items from the fish bowl into the bucket.
Next take a clean paper towel and scrub the inside of the fish bowl until it’s squeaky-clean. Rinse the fish bowl well with tap water, pour the old water with the fish, aquatic snails, shrimps, and plants from the bucket back into your fish bowl, and fill your fish bowl 2” from the top with bottled drinking water.
 Pick a good place for your fish bowl. Sunlight can contribute to green algae growing in your fish bowl so pick a place away from windows. Cool water is good for fish in fish bowls so don’t put your fish bowl near the heater. Put the fish bowl on something flat and sturdy so it won’t rock, crack, or get knocked over.

 5. Don't Put Goldfish in a Fish Bowl. 
You can put a maximum of only one 1” goldfish in a one-gallon fish bowl, and it usually will not do well. If it does well, it will quickly grow too big for a fish bowl. Goldfish are not appropriate fish for fish bowls. Our experience is that almost everyone who puts goldfish in a fish bowl has problems.
Good Fish for Fish Bowls.
One Male Betta or one Female Betta, a few Ghost Shrimp, and aBlack Mystery Snail are appropriate for a large fish bowl. Another good combination for a fish is three White Clouds, a few Ghost Shrimp, and a Mystery Snail.
Live Aponogeton Plants, Java Ferns, and an Umbrella Fern add natural beauty. A Dwarf African Frog can live in a fish bowl but will need to eat live Black Worms twice a week. Click here for more information about Black Worms.

 6. How to Feed the Fish in your Fish Bowl.
Feed the fish in your fish bowl twice a day with foods that float such as floating fish food and freeze dried blood worms, which are actually mosquito larvae. Do not feed food that sinks and will be difficult to see on the bottom of the fish bowl.
Start by feeding your fish a very small pinch of food. Carefully watch them eat. If they eat it all quickly, then give them another small pinch. Keep giving them small pinches as long as they eat all of it quickly.
Do not give them another pinch until they've eaten all the food from the previous pinch. Feed them as much as they’ll eat without leaving any uneaten food in the fish bowl. Click here for more information about feeding fish.
Food that sinks to the bottom and is not eaten will cause water pollution, so be sure all the food is eaten. Use your net to remove the food that is not eaten after ten minutes. It’s fun to feed your fish a few freeze dried blood worms for dessert.


7. Fish Bowls Need 1/4-inch of Cultured Gravel.
Your fish bowl will be much more difficult to care for if it has a lot of gravel. But 1/4 inch of gravel will actually increase the bio-filtration of the water.
So 1/4" of gravel is good in fish bowls, but more than 1/4" will cause problems. When you clean your fish bowl or change some water, stir the gravel before you pour out the old water.
Remember, if any uneaten food sinks to the bottom of your fish bowl, it will be hidden in the gravel and difficult to see. So you must be careful not to feed more than your fish can quickly eat.
Unlike Fish Bowls, Aquariums with power filters and BIO-Wheels do not need gravel and should not have more than 1/4" gravel. Click hereto read more about Cultured Gavel.


8. Don't Crowd Your Fish Bowl.
Since most fish bowls don't have filters or other life-support systems, you must keep the so-called bio-load low. That really means a fish bowl can't cope with large amounts of fish waste.
We keep 1.5 gallon fish bowls, that hold 5 quarts of water, with one Betta, 2 Aquatic Snails, and some live Java Fern plants. There are two pictures of large fish bowls at the top of this page and a picture of Minerva's large fish bowl at the bottom of this page. A goldfish produces too much waste to be kept in a fish bowl.