Swim Spa - Fine Solids

[PortlandORSwim]

I have 2500 gallon swim spa and can't overcome a water quality challenge. PROBLEM: In about the past month, I've been seeing tiny white suspended particles that stay suspended after the swim pumps shut off. When I changed the filter out, the top of the housing had strange tacky white flecks on the housing. I maintain 100-120 mg/l Alk, 160-180 mg/l hardness, Free Cl 3 - 5 mg/l, pH at 7.3-7.6, and about 0.2 mg/l copper sulfate (for algae control). Cyanuric acid is low right now (little sun on it). I also have a UV/ozone for advanced ox, but I suspect ozone isn't working.

ACTIONS TAKEN: I shocked the pool to 25 mg/l with CalHypo (73% Cl), ran a system flush product, drained 90% of the water, scrubbed walls. Filled, put in a new filter, rebalanced, did another shock with Calcium Hypochlorite at 25 mg/l, drained, cleaned the new filter with acid and thoroughly rinsed for 15-20 minutes. Shock each sat for 18 hours. This whole process took place over two subsequent weekends. I refilled, rebalanced, put in CalHypo to 5 mg/l, and tweaked all levels.

RESULT: The tiny white flecks are still there (after swim jets are run). When everything is settled and the underwater lights are on, the water looks clear as air, but as soon as I turn on the swim pumps (800 gpm), there's tiny whitish stuff stirred up that hangs in suspension for 10 minutes. Am I expecting too much of a swim spa?

[Teapot1]

Ok, whats the swimspa made from? If its plastic then you dont need to worry about maintaining Alk or hardness at those levels. Alk in particular in a swim spa will allow the pH to rise through aeration. If you go through the process of lowering Alk to aroind 40ppm your pH will stay pretty much stable all the time.
Cal hypo raises the calcium level so it can drop out of solution. The fact this happens when the swim jets are on only sounds to me at this point that you are clearing some biofilm from the pipework which may have calcium sitting on it hence why you can see it. I would switch to sodium hypochlorite. Also with some spas and I would imagine some swim spas the filtration circuit is often shared with the swim jet circuit so filter collects all the stuff and swim jets blast it it back out again. On the spas I have worked on, many I replumbed to keep filtration only as filtration and the spa circuit separately plumbed so as to avoid what I have just mentioned, filter breakthrough
Hope that helps with some ideas, not easy from behind a PC.