Choosing a size of hydroponic tank

When you want to find the right tank for your hydroponics system, there’s one big thing to think about. It’s all about size of hydroponic tank. If you don’t have a good fit, you’ll run into problems. It may be a pain to have an overly large tank, but it’s far worse to have a tank that’s too small. A hydroponic tank that’s too small won’t be able to feed your plants properly.

What’s the biggest factor in sizing a hydroponic tank? Your plants. You need to calculate how many plants you’ll have, and what they need. It’s common practice in hydroponics to go over the volume strictly needed. In fact, many people take the volume required, and double it.

Here’s how you should start when you size your hydroponic reservoir:

If you haven’t set up your plants yet, look at how many you want to have. If you have them all set up, take an inventory. Look at the size of the plants. You need to figure in their mature size. Mark how many large, medium, and small plants you have, or will have. Some plants can be tricky if you’re looking at mature size. When in doubt, assume they’ll get bigger.

How much water does each plant need? Use these guidelines to help:

  • Small plants – plan on at least ½ gallon for each plant
  • Medium plants – plan on 1 to 1 ½ gallons for each plant
  • Large plants – plan on at least 2 ½ gallons for each plant

With this in mind, it isn’t too hard to figure out the volume your tank needs to hold. Just add up your plants and do the math. Let’s look at a quick example to see how it works:

For instance:

You have 10 plants total. You tally up the sizes like this.

  • 5 medium plants
  • 2 large plants
  • 3 small plants

For your medium plants, you need 1 ½ gallons each. For 5 medium plants, that means 5 x 1 ½

Total volume needed for medium plants = 7 ½ gallons

For your large plants, you need 2 ½ gallons each. For 2 large plants, that means 2 x 2 ½

Total volume needed for large plants = 5 gallons

For your small plants, you need ½ gallon each. For 3 small plants, that means 3 x ½

Total volume needed for small plants = 1 ½ gallons

Now, add up the total volume needed for all the sizes of plants. 7 ½ + 5 + 1 ½ = 14 gallons

Keep in mind that 14 gallons is the bare minimum you need to support your plants. If you want to be safe, do as many hydroponic gardeners do, and double that amount. If you do that, you need to have a tank that can hold at least 28 gallons.

Learn more about hydroponic tanks.