Originally Posted by Bill Cody
Hi-Blow when running at maximum depth will result in shorter times between rebuilds and maximum depth stress will shorten it's life span. Rebuild kits are expensive. HiBlows are designed for shallow lily ponds and septic tanks. IMO it is better up front to spend a little extra money for a unit that can better handle the 8.5 ft depth. Cheaper often ends up costing more money in long term.

Bill, respectfully I suggest you give the Hiblow pump a second look.
At .2 acres,the OP is an excellent candidate for the Hiblow system.
Reliability wise, I’ve seen nothing to support the need for rebuilds that you suggest. I’m coming up on four years running nearly 24/7 without a rebuild. For the first full year I was running diffusers deeper than the OP’s pond is. Another factor to keep in mind is monthly cost of operation, for which the Hiblow is a fraction of those compressor style pumps. Hiblow

Wings,
If you do decide to get a Hiblow, make sure there’s an LL at the end of the model number. The LL stands for Long Life, well worth the added cost. I use the 120LL and recommend it to everyone.