I don't understand the question. What 'salt' deposits?
My overhead tank has stagnant water in it. No salt deposits.
I thought surf easy wash is blue in colour. It's not meant for a front loader. Just top loader or handwash.
I would use SurfExcel Matic for FL instead of Tide or Easy wash
A front loader detergent creates less foam so less chance of affecting bearing seals. Since you did not notice the machine getting louder your bearing seals are fine.
How to make a spider last 10-12 years instead of replacing it in 7. You only got seven years of use from your machine. Which is the median. I think it is possible to get more.
I suspect this spider problem has arisen because detergents no longer contain phosphates. When they did these spider problems were less. A spider would last 15-20 years. A friend had a 20 year old IFB FL whose bearings gave way and couldn't be replaced. The spider I think was ok. No wobble when you turned the drum.
Somehow those phosphates delayed the spider corrosion. I doubt people did tub cleans that often back in the day, only if there were smells. I've seen people restore older machines that were filthy, the owner threw them out because of the smell but otherwise worked perfectly well.
I don't think the spider material has changed. It's always been aluminium alloy except for a few companies that used stainless steel.
