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How big will your aquarium be?

You will have your child work out how big an aquarium to get, but you will want to direct the conversation. There are several considerations.

  1. The larger the aquarium, the easier it is to care for—up to a point. The smaller the tank, the easier it is for something to go wrong. Things can go wrong quickly with a 5 gallon tank that will take longer to develop for a 55 gallon tank. But there are maintenance issues. A 20% water change on a 20 gallon tank is 4 gallons. A 20% water change on a 150 gallon tank is 30 gallons.
  2. Where the aquarium will go will be an issue. Aquariums are heavy. A liter of water is a kilogram. A liter is about a quart, so a gallon is about 4 kilograms, or about 8 lbs. A 20 gallon aquarium is 80 kg. Or 160 lbs., and that’s not including the weight of the aquarium itself. Generally, aquariums go away from direct light to control temperature and algae, away from drafts to control temperature, and along a wall (to prevent problems with the floor). You want the aquarium away from fumes that be absorbed into the water and kill the fish, so the kitchen is probably out.The result is usually either the child’s room or the family room, which may limit the size.
  3. Finally, there’s the cost of the aquarium. I put together a spreadsheet and listed everything I purchased for my 20 gallon aquarium. I’m up to $525 dollars as I write this. Please realize that I went with the best available equipment and supplies, and I probably won’t need to buy anything for a year.There are ways to cut the costs. I purchased from a local store that charges more but can give me advice when I need it. The costs in the graph below are from online, and are cheaper than what I paid. I’ve seen aquariums for sale at estate sales, Craigslist, and at aquarium club meetings. Making friends with someone who has aquariums may be a way to get a deal on someone’s spare tank! There are a number of ways to get less expensive aquariums, but you must also ask what happens if the tank leaks. Stores have sales. If you wait a couple months, you may find a deal on an aquarium kit.Aquarium Kit Cost

I hope this post helps you think about the important points before you begin this project.

I named this series “Science in 80 Liters” because an 80 liter (20 gallon) aquarium is a nice compromise between size, ease of maintenance and cost.

You may wish to go smaller or larger, depending upon your situation. You may guide your child or children through the decision, or you may simply choose a size and go on from there.

Written by Rob Carr


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Before You Start (1)

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