[Rockworld]

Pondigger
From looking at pictures and your comment about reducing spray height the following tip will be useful.
It's always a good idea to size pumps correctly for its intended use. Its cuts down on running costs and the initial cost of pump. In your case using a valve to reduce height means the pump is over sized and this results larger ongoing electricity bills for the owner.
In your pictures it looks like water is flowing through a 2 inch opening at about 6 feet high, not 2 feet high as you said in your last post. Naturally the pump required to shoot water 6 feet up is going to be considerably more powerful than the pump required to pump water 2 feet high. So when a water feature is built it is not just about the initial cost but much more , like ease of maintenance, quality of materials and running costs.

Maybe you will come back and tell me that you changed the pump to suit the real height of the running water feature

PS why didn't you mention earlier in this discussion that the real water height was much lower than your photograph