Chil,
Depends on what you are doing with it.
If you have just a pool, then you can certainly divert that water to a water feature.
If you have a pool/spa, then if you want to use the spa, and use the water feature you have a problem.
If it is a large water feature, and you just want one pump, then you are running too much HP and wasting money to filter your pool.

In comes Pentair's new VS (variable speed) pump. TahDah
Yes it runs slow to save you money while you filter, and it runs fast to make that wow water feature.
I should get paid for this.

Others will have their reasons just wait.

We are experimenting with the Variable speed pumps as well. Usually we run separate pumps for our water features because of the size we build. We also add a booster pump to the spa. I get a kick out of the low ball builders who say "we will save you money and use everything off one pump". You end up with a nice pile of rocks and a trickle of water. And then when you are in spa mode and you want to enjoy the features you can't because they need the pump for the spa.

Thanks just-a-bp,

Stupid question #2:

If you use one variable speed pump, and divert to the water feature, this water is not run through the filter?
Why not?
Why not have the water always go through the filter - run slow if it returns via the pool - run fast if it returns through the water feature??

chil,
Water would still go through filter.
The more you run your waterfall, the less time you need to run the filter to clean water.

echo what justapb said (and nice meeting you the other day...haha).

I strongly prefer the VS intelliflo the more I use them. Simply put, you can have a high rpm to clean the pool if you have an infloor or similar system that requires a greater flow rate, a slower rpm to filter based on your required turnover, and still have 2 more speeds to program for your waterfeature(s). For instance, I have a VS on 4 deck jets. I can use the different speeds for different heights of my deck jets. This also works great for controlling noise levels of your waterfeatures and also spa jet pressure.