The man at the nursery told me of bog gardens, and I'm pretty sure that is the way I'll go. He told me to google Nelsons Water Gardens (www.nelsonwatergardens.com ) and read about their bog filtering system. Look under "Nelson Know-how". THAT's what I want, that's what will work for me, and that's what I plan to do. Maybe that will answer a lot of your questions.

I came here today to ask questions about construction materials, since I'm on a budget.

Since a bog garden should be about 12'deep, according to Nelson, and the stock tanks are deeper, you will lose a lot of the visual beauty and reason for the bog.
Consider eliminating both stock tanks, and replacing them with a bog type system. The stock tanks will hold and keep all the nutrients your bog plants need to thrive.
Maybe use one tank as a water catchment and filter for rain water from your roof before allowing that water to go into your pond.

Maybe use the other to filter your laundry gray water before sending it via a rock strewn plant filled stream, into your bog.

If you do that, be sure to use biodegradable, fragrance free/dye free detergent, and no laundry softeners, liquids or sheets, of any kind. Did you know that those things damage your clothes? In fact, wash new clothes separately from those with which you have used those products for a few washes, so any remaining residue won't transfer to the new items.
Ella5

It occurred to me that some bog plants are either very invasive, or pretty tall, and want more water than others. You could use one of your stock tanks for those types. Divert some pond water into it first, but allowing the majority of the water to flow directly into the shallower bog.

This is giving me an idea for mine. Because my bog will have to be so large, I am considering combining 2 of his forms, the waterfall, (the raised) and the perimeter. I thought of having my fall sort of in the middle and diverting water in 2-3 direstions: both sides, and a lesser one directly toward the pond. some water from one side could be channelled into the tank at the side, and from there, overflow via tube into the bog. The tank and it's contents would help hide the buildup for the fall.

If you'd rather have the tank in a different place, you could still do it. Capture some of the water via a pvc tube stuck into higher up into the waterfall and let it flow by gravity to a distance away and into the tank.
Ella