Hello! I am posting plans for a 250 gal stock tank pond. I just wanted to know what you guys think and especially whether or not there are any major flaws with my current plan.

So the tank would be a galvanized steel round end tank around 2 x 2 x 7 and a roughly 25gal garden vase would be used for the biological filter. It will be bare bottom and I would like to use a 650 gph fountain pump at the bottom of a 5 gal bucket filled with hydroleca and capped with small rocks. The prefilter bucket would be placed at the opposite end of the tank from the biofilter overflow. A few buckets filled with hydroleca would be pots for Iris, Dwarf Papyrus, and purple taro. Moneywort would also be planted in these and trained to cascade over the sides of the tank. These would be covering the prefilter and have a few holes punched in the sides but not the bottom (I don't want roots getting into the prefilter). The outlet from the fountain pump would be emptying into the bottom of the garden vase. The vase/biofilter would also be filled with hydroleca and a few types of canna lily would be planted in it with more moneywort. There would be a terracotta pot filled with loam capped with gravel for a waterlily placed near the vase overflow to stop ripples from continuing across the pond. As far as fish stocking goes I would like to include 3 hi fin banded sharks and 3 fancy goldfish (black moor, redcap oranda, and a calico Chinese fantail). If algae were to become a problem I would introduce a few Chinese trapdoor snails.

In the attached photo the red crosshatch pattern represents a lattice and vine.

Does it sound like I would have enough filtration for the fish mentioned? Or should I use a more powerful pump?

Looking forward to your comments!
Cheers!