If you are watering from the upper ponds, don't grow plants there, breed animals instead.
When the water gets to the bottom pond, that's where you want to clean it of animal waste by growing plants.
That way the fish, prawn whatever are getting filtered water.
If you pump to a point above the upper ponds you can use waterfalls to add oxygen to the water.
If you are not too worried about what you get from the lower pond, grow reeds and cat tails, they provide food, fuel, biomass, all kinds of things, and as mulch they are not going to sprout on
land.
If you put one of the top ponds above the other, you could grow duckweed in that one, allow it to overflow into the slightly lower one, which would hold the fish.
A floating open bottom
greenhouse could help keep the ponds free of ice. It could have a hoop house top and dark metal suspended halfway into the water.
You could even use a coil of black hose , fitted with a PV powered pump, to aerate and heat the water.