Corrosion and rust in ^ ground pools

I've been reading and thinking about upgrading from my Intex Frame pool. I may have a grasp on the salt generated chlorine. Maybe a salt pool is probably not a good thing for an above the ground pool in MI? I belive that corrosion is the major problem of ag pools. Salt water is more corrosive than plain h20? I think I understand that resin is not corrosive. (But a mostly resin pool is very expensive and out of my budget.) And that corrsion accures when moisture hits metal. Some pools have stainless steel side panels where the pumps and filter go thru the wall. Why is this better? We live in a state that has snow and freezing temps 1/2 the year, I imagine the climate would play a part in what kind of pool you would choose. Do most pools rust from the bottom or where the skimmer and filters connect? I know that when you park a car outside for 10 years something is eventually going to blow out. There has to be ways to slow the failure down..? Thanks..Kimrst

There are a lot of factors that contribute to rust including the pH, dissolved oxygen and to a lesser extent other oxidizers (including chlorine), conductivity (salt), temperature, and others. However, in pool water it appears that pH is the most important factor and that maintaining a pH above 7.0 makes corrosion much less likely. The saturation of calcium carbonate that is done in plaster/gunite pools also forms a thin protective layer on metal surfaces that inhibits corrosion.

So I would say that keeping your pool water balanced will likely not corrode pool surfaces that are in constant contact with your pool water, including your heater elements. On the other hand, splash out onto deck or other surfaces that are exposed to air is another matter and in that environment a salt pool splashing out salty water may corrode metal faster.

Hope that helps. It would be interesting to hear people's experiences with AG pools. I suspect that with stainless steel, there isn't much of a problem. It would only be with basic steel (iron) where they might be some issues.

Richard