Welcome to R2R!
Anemones usually like a bit more light than corals, but IMHO that's not a big deal. Some anemones do like to move around until they find their 'happy place'. And they can be slow to change. I've seen a condy that turned inside out for several days and then went back to being perfectly normal.
What might be helpful for us to help you would be a run down of your water parameters, salinity, temp, nitrate, phosphate, calcium, alk and magnesium.
I'm going to say I think your conclusion about the stirred up ocean water is probably not well based in facts. But it also depends on where you were when you were collecting the water. Near shore water tends to have a lot more 'stuff' in it than water collected some distance off shore (like a mile or more). And around reefs it will even be a bit more different (probably better).
I do some collecting in the Florida Keys and in the Gulf of Mexico off the coast of SW Florida. I try not to take any water from the surface. I'll push the container down underwater and cap it before I bring it back up. But then that's just for use in transporting things home. Once I get them home they get acclimated to my water and I try to get as little 'wild' water as possible in my system. But that's just me. There are a fair number of people who use natural sea water as well.
Welcome aboard and good luck.