What are you using to mix your saltwater together in large containers? I have debated on a paint stir paddle to use on my drill but the ones I've seen are only about 16 inches long.
My mixing station is similar to hbrochs . I have a mag drive that recirculates the water/salt and have a heater installed in the container. Ill have to get a pic to post.
I mix by hand and a pipe of pvc to stir till I get the correct salinity. Then I have a very strong powerhead thrashing it in a brute can over night while a heater matches temp. Check in the morning and it’s always dead on and clear. Then it’s water change time!