"Improved" Phosphate Free Dishwasher Detergents and STPP

[labboy]

Thanks to everyone who posted information about their experiences with the new phosphate free formulations of dishwasher detergent.

Recently, unknowingly I purchased a box of the newly reformulated Cascade and had chalky white film all over the inside of the dishwasher, dishes and silverware after the first use. I realized it was "phosphate free" when I closely looked at the box trying to figure out what happened. I know the problem is the new formulation because I ran another cycle with what I had left of the old product and everything came out flawlessly. My water temperature is about 130 deg F, I use rinse agent, run the water at the tap before starting the dishwasher and use the sani rinse option. Our water is very hard at about 12 to 15 gr/gallon. The phosphate makes a big difference with the hard water.

I went to my local Big-Lots and found they are clearing out the old formula of the great Cascade Complete with Bleach Hydroclean Action. I stocked up. I also found a source of STPP for when I run out of the old Cascade.

Two questions:
1. When I use the STPP, how much should STPP and detergent should I put in the dishwasher? I have a new KitchenAid with the main and prewash cups. I typically fill both cups completely with detergent.

2. Is STPP OK to use in a front loading high efficiency machine? I have a new LG (model WM2050). Again, how much should I use for a normal wash? Should I put it right in the bottom of the tub or with the liquid detergent in the dispenser? Will the STPP harm clothes in any way over time?

Thanks very much.

Bob

 

[gmmcnair]

I don't need the STPP in my Dishwasher

...my water is super soft, but I do like it to boost white clothes in the washer with the Sears detergents.

I wouldn't mix it with the liquid detergent and glop up your dispenser. I add it to the tub all the time in my top loader without issue. I've never had any problems with fabric damage....it's much kinder to textiles than washing soda.

It takes a tablespoon to make a noticeable difference in my clothes so I'd start with a teaspoon in the dishwasher. I'd bet it helps a lot.

 

[rp2813]

I think in the other thread on dishwasher film our fellow member Rich calculated somewhere between a teaspoon and a tablespoon. I'd start with a teaspoon and see how it goes. If I were using this stuff, I'd probably put a teaspoon of it in the dispenser and then top it off the rest of the way with the lame phosphate-free detergent. My Thermador dispenser is very touchy. Filling it over the line (which is still about 1/8" below the top of the cup) will cause it to jam and not open, so that's why I'd make sure I got the STPP in the cup first.

 

[sudsmaster]

Thanks Ralph.

A tsp to a tbs is variable... basically I recommend adding one part STPP for every 2 parts detergent. It can be more convenient to mix up a large batch in those proportions beforehand, and then just use your usual dosage (adjusting as needed) in the dishwasher or the clothes washer as appropriate.

(Note: do not attempt to wash fine china in a front loading clothes washer!).

 

[launderess]

STPP avec Lessives Liquids

Use powder STPP all the time with liquid laundry detergent, and one hasn't observed adverse effects in my Miele.

Rarely use the dispenser for liquid detergents Miele sells,but just put the STPP into the drawer, and the liquid follows as the machine starts to fill.

The only product one puts directly into the wash tub is Ariel Excel gel from France. It comes with a dispenser ball that sits on top of the laundry.

However given the wide differences in washing machine designs, YMMV.

L.

 

[labboy]

Update

I picked up the STPP today. First, I tried using one tsp in the dispenser along with liquid Tide HE. At the end of the cycle I found there was a great deal of undissolved STPP remaining in the dispenser. I also tried a few (off-line, bucket based) tests of water and STPP and found the optimal dose for the washer (considering local hardness and washer fill volume) was 1 tbsp. I placed 1 tbsp directly into the tub when adding clothes then added my normal detergent to the dispenser. It worked great...little foaming, clean rinsing and everything (especially the whites) were cleaner than ever before.

For the KitchenAid dishwasher, I used one tbsp of STPP evenly divided between the prewash and main wash cups then topped off the cups with the (horrible) phosphate free Cascade. The dishes and machine interior were the cleanest they have been since we installed the machine six months ago.

Thanks to everyone for their input and suggestions.

Bob

 

[westyslantfront]

Hi there. I purchase STPP powder from the chemistry store online.com

I add it to the dishwasher and also mix it in with laundry powder for great results.

Ross

 

[jetcone]

traditionally in early

powdered detergents for laundry STPP ran 25% - 45% of the total weight of detergent, the surfactant usually comes in at
1%-3% total weight.

So a lot was used in the 60's formulations!

 

[sudsmaster]

Yes, early phosphated detergents used up to 50% STPP.

But after the first concerns were raised about eutrophication, the industry throttled it back to about 33%, which works just fine for most people (unless one has super hard water, in which case stuff like Calgon, which used to be mostly STPP, was available).

The usual dose of the phosphorus element in a 33% detergent is about 8%, which is pretty much what phosphated dishwasher detergents, until very recently, were at.

I did find some phosphated Cascade at the local Mexican shoppe, but at $4 for a very small box, I passed. I'll hit Big Lots soon and see if they have any more on clearance.

 

[whirlcool]

Our water is 9 grains so we use 1/2 to 1 teaspoon STPP in the dishwasher. We save our stash of phosphated Cascade for the really dirty loads. But we use either Palmolive Lavender Gel or Walmarts Great Value powder for everyday loads. With the STPP we get great results.
If you have a SS interior in your DW, the addition of STPP will shine it right up.

For Laundry we mainly use FOCA, non-phosphated. We use 2 tablespoons with that per load in our TL machine.

 

[jetcone]

Good point Rick

"The usual dose of the phosphorus element in a 33% detergent is about 8%, which is pretty much what phosphated dishwasher detergents, until very recently, were at. "

I forgot the exact chemical ratio of Sodium to Phosphorus for STPP but that is a good point about the actual amount of phosphorus that is available after degrading versus the amount put into the formulation as STPP!