Derek,
Welcome!!
First off, congratulations for having the drive to get started. Now learn, learn, learn. I have done most everything you have done, and I have done everything wrong you are about to do. That said, It is fun learning, but the panic side of it can be a little unnerving.
I have two threads from last year and this year showing my attempts. Last year was panic on a grand scale. This year, we have done a better job getting ready for our winters and they are nothing like what you are going to see. Depending on the type of Tilapia you are allowed to use, you are going to have heat issues. My goal for our Mozambique Tilapia is 80 degrees F plus or minus. I know I will be okay down to 65 degrees F, but I am taking no chances. I have solar power and shore power available running half of the system.
About selling them, there are a lot of hoops to jump through, I would raise them for your own consumption, it just easier. After you get established, think about selling some if you would like.
Also look at RDF filters, they are easy to make and better than settling tank. You Tube is your friend.
About Media, Cecil gave you the gouge. I would go with his recommendation. Most of the time it is talked about in cubic feet not gallons.
Last item for now, Learn about AIRLIFT to move your water (again, You Tube is your friend). With one air pump like Cecil showed you, you can move all of your water and keep your MBBR happy with some air to spare.
Hope this helps.
