I have the badu swim jet in our 13x26 indoor. It was the larger of the 2 at the time. It is plumbed with 6 inch lines to the 4 hp motor and back to the jet. It took me about a week or two to get used to swimming against the jet. At first I was worried it wasn't a "fast" enough flow, but as you get used to it it is more then enough. While just about any good swimmer could swim right up to it, to stay at 5 feet back for even 5 minutes is a chore. Sort of like sprinting vs jogging speeds.
The only real trick for me was to stay centered on the jet, fortunately I have a center tile line on the bottom that helps out a lot. I would really recommend it to anyone who wants to swim in place. I did try the foot straps and other non-pump methods and you just don’t get the same feeling.
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