I used to use the vortex filter on a large pond I had up about 10 years ago. I had an urge to put a big hole in the earth and spend a lot on clay (bentonite) to seal it. It held about 250,000 gallons and I had to keep it full with my solar windmill pumping system. Way too much work, but I learned a lot about filtration. My pump bill was $50 a month just to run the filter. I sure grew some big Koi. Down side was all the migratory birds put me on the list, (yes the Blue Heron like to eat the colorful expensive ones first.
)
At any rate that area became a barn after I brought in a couple of 40' containers and put a gambrel roof over it. No more giant ponds for me, that's a young man's game; but I did it. My mentor owned Koi Breeders in New Berry springs, He had about a half mile up in ponds. The big Scott and I were friends. He was
about 15 years older and retired to Hawaii after he sold out.
That vortex filter comes in handy and keeps me from dumping a pond if something goes wrong. I usually just use it for isolation tanks.
As I was explaining in my original blog about a different approach.
my latest goal is to
not spend $$$$ pumping water around. After all
being an energy consultant I do walk the walk.
To date my pond efforts are 10 small ponds instead of the big one, and I don't pump any filter water. It makes use of the flowing water from the springs, which I augment once a week in the summer with the solar windmill. I can get buy without the solar windmill, but the extra water freshens the ponds and makes the fish more lively.
I realize my situation is unique, but using gravity filters really cuts down on pumping costs.