Building the grow bed
The Grow Bed
Pretty much any watertight container can serve as a grow bed for your aquaponics system. Well, there are some criteria that it should meet. These may be obvious, but I will list them here anyway:
Watertight
The container needs to be able to hold water and your grow media without leaking.
Structurally Sound
Water is heavy. Make sure your grow bed and stand is strong enough to handle the full weight of the water, grow media and plants.
Food Safe
If you are planning to grow flowers and have only ornamental fish, you don’t need to worry about food safety. However, most folks grow edible plants and are probably planning on eating their fish at some point in the future as well. It is therefore very important to do the proper research on what type of materials to use in your aquaponics system. Basically anything that comes in contact with your plants, water, fish and the rest of the system needs to be made from food safe materials.
Depth of Grow Bed
Why does the depth matter? Well, for several reasons. If it is too shallow then the roots of your plants can only spread horizontally. Taller plants may become unstable and fall over when they get bigger. You also end up with less “available bio surface area” for your biofilter. I will get into more details in another post about bio filtration. So what is the right depth for your grow bed? I would aim for 12 inches/1 foot. You will probably end with about 10 to 11 inches depth for your grow media, considering that you probably want to leave a little space to avoid that the grow media overspills. Especially when you plant things and move the media around.
![Grow bed](http://www.mt-aquaponics.us/wp-content/uploads/2015/03/aquaponics-grow-bed-annotated-300x225.jpeg)
My DIY grow bed. It is 4 ft x 5 ft in area and 1 ft deep and it is made from scratch out of ply wood.
Grow Bed Construction
After doing a lot of research on the Internet, I decided to build my own grow bed from scratch. I have a very particular spot in a small side yard and I wanted to maximize the area. I sketched out the dimensions, went to our local home improvement store and had them cut the pieces to size. Due to the expected weight of the water, grow media and plants I added reinforcements to the bottom of the grow bed as can be seen on the next photo.