STTP in Washer

[drhardee]

Where to purchase STPP??

The Chemistry Store, located just outside of my home town of Columbia SC, sells STTP. They are easy to work with, and their prices are quite reasonable.

https://www.chemistrystore.com/Chemicals_S-Z-Sodium_Tripolyphosphate_STPP.html
https://www.chemistrystore.com/Chemicals_S-Z-Sodium_Tripolyphosphate_STPP.html

 

[littlegreeny]

Is STPP supposed to clump?

I purchased some a while ago from Amazon and it clumps pretty badly when water is added. Is that normal?

 

[launderess]

No, it shouldn't

Have STPP stored in gallon Ziploc bags and Rubbermaid containers that is not clumped in containers, nor when placed in water. There might be the odd clump per container, but nothing huge.

There are some complaints on Amazon that versions of STPP sold are of a more larger grain variety. That could be why you're having issues with clumping, as others have reported same.

https://www.amazon.com/Sodium-Tripo...show_all_btm?ie=UTF8&reviewerType=all_reviews

STPP in my stash is a fine powder, again never had any issues with clumping

 

[littlegreeny]

Thanks Launderess!

I have it stored in a Rubbermaid container as well and it's fine in the container but once added to the washer it turns into a hard clump. I must have been sold an inferior or perhaps imitation product? Maybe it's actually TSP?

I'm getting a new Miele in 13 days so perhaps it's better to just throw what I have out. I don't want to risk ruining my new machine.[this post was last edited: 11/21/2021-13:08]

 

[littlegreeny]

Perhaps it's just user error?

I took a small glass of hot water and poured in about 1/4 tsp of the STPP and it dissolved immediately. There was no clumping or sediment in the bottom of the glass and the water felt slippery too.

 

[henene4]

Some powders do that if you add them to water to quickly.
Adding them slowly or spreading them out thin onto the load before the machine starts to fill might work to.

 

[eurekastar]

Clumping

I think that may have something to do with the quality of the product or how it's stored.  I had that happen with some STPP that I bought off Ebay that came in large plastic bags.  However, I've never had that happen with STPP that I've purchased from Amazon, which comes in plastic tub.