No, they are most definitely not the same thing. I've found my washing soda at Kroger and Meijer and I know you can get it at WalMart too. It will be in the same aisle where the laundry detergent is, often up on the top shelf in a large yellow box with the same arm and hammer on it that you see on the baking soda box. I believe you can also find it at Pool supply stores if you really can't find it at any local grocery store. It's used to adjust the ph of pools and will be called either Sodium Carbonate (it's technical name) or Soda Ash. Make sure if you get it at a pool store that it's 100% sodium carbonate and not mixed with anything funky.
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Re: RP: ? homemade CD laundry detergent from EFF blog
Ditto PP, they're not the same thing.
I also find mine at the grocery store (Kroger).
I find it in the laundry isle near the bleach, oxiclean and other laundry additives.
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