I have an inground, gunite spa that spills into my pool. It has a 2 hp spa pump, 1 hp blower, and eight (8) spa return jets as follows: six located approximately 7" above seat level and 2 located approximately 6" above floor in seat wall. The attached picture from during the spa construction shows the jet locations.

My problem is that the flow from the jets is uneven. The highest jets have more flow than lower jets, resulting in the foot area jets having very little flow. Is this to be expected? Can it be corrected, perhaps with different size jet inserts?

Thanks for any advice!

Are they all plumbed together? You can install different sized jets and adjust the flows somewhat.

I don't know the answer to your question about plumbing, but here is a picture of the plumbing.

It looks like they're all plumbed together. Playing with the jet size should get you an acceptable result. A few of the top ones with a smaller jet should raise the pessure to the bottom ones.

I don't know what kind of nozzles are attached, but is it possible the're unevenly opened? Mine are adjustable by turning the outside part, so you can influence how much water runs trough them.