Just use descaler once in every month and run the empty machine on daily/mixed load mode with hot water option. You don't need all this because you have to use descaler either way
I'm in a confusion. Should i buy both(Fresh n clean J & Aqua merit) like you just showed? The IFB guy was trying to sell me two Aqua Merit for my IFB washing machine.
Filter cartridge change depends on your quality and hardiness ( I change every 4 to 6 months I use sometimes bore & municipal water my water quality is AVG)