I've had the SWG on the smaller pool for over 15 years. The saltwater rust everything it comes into contact with. Pool water splash on windows? Better wash it down with a garden hose. Basically anything metal that pool water comes into contact, I'd better hose it down afterwards, or it will rust. As you can see, I'm not a huge fan of SWG. Low pool maintenance at the cost of equipment, tools, and greater calcium build up / hard water. But the pool is always clear, sanitized, and the key was lower maintenance. I wondered if SWG is so great, why don't they use it on commercial pools?
When I acquired the larger pool, it didn't have an SWG. It didn't have major calcium build up. It was not hard on the equipment when water splashed or leaked from the pumps lids (8). I think more importantly, it's not going to rust out the heater components as fast. The chlorine tablets are definitely more expensive, but it has chlorine and stabilizers in it, too. I use shock when needed.
In Southeastern Texas, water evaporate like crazy in the summer months although fall/winter months are not as bad. My neighbors' and my water bill is always high during the summer months. I definitely hear you. I'll limit the use of copper sulfate. Thank you for the information.