There are a variety of DIY kits and instructions online. You might take a look at https://www.youtube.com/watch?v=Ap-twxpof6w for a great way to build a modestly-sized inexpensive outdoor system. For a more modest but really rewarding indoor system, check out the ECO-Cycle Aquaponics™ kit from ECOLIFE. https://bit.ly/WQRPm9 
