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I red alot about the chemicles but, I didn't know what "TSP" was so... here is the information for others who don't know what it is. ( I got it from Wikipedia)

Trisodium phosphate (TSP), available at most hardware stores in white powder form, is a cleaning agent, stain remover and degreaser, commonly used to prepare surfaces for painting. It can also be called trisodium orthophosphate and has the chemical formula Na₃PO₄; however, it is generally found in hydrated forms. It is a highly water-soluble ionic salt. Solutions of it dissolved in water have an alkaline pH.

Other sodium phosphates, sometimes known by E number E339, are food additives and used as an acidity regulator (buffering agent), emulsifier, thickening agent, nutrition enlargement agent and sequestrant (metal-chelating agent). Sodium phosphate enemas are sold over-the-counter in the United States, as a laxative to treat constipation. However, these should not be confused with the related compounds sodium dihydrogen phosphate, also known as monosodium phosphate or MSP, and disodium phosphate.

[edit] TSP for cleaning

Trisodium phosphate hydrate

Similar chemicals were once common in laundry and dishwashing detergents, but the phosphate, being a fertilizer, would cause algal blooms in the bodies of water into which the drains led. In the early 1970s the use of phosphate-containing products was limited. Now products sold as TSP Substitute, containing 8090% sodium carbonate, are promoted as a direct substitute.

Cleaning products labeled as TSP may contain other ingredients as well, and may in fact be less than half TSP.^[2] So even "regular" TSP found at the hardware store may be half TSP and half "TSP substitute".^{[citation needed]}

Although it is the active ingredient in at least one toilet bowl cleaning tablet^{[citation needed]}, TSP is generally not good for cleaning bathrooms because it can corrode metal.^{[citation needed]}

TSP is commonly used after cleaning with mineral spirits in order to then clean up all the mineral spirits.^{[citation needed]} TSP may be used with household chlorine bleach in the same solution^{[citation needed]}, and this is particularly good for removing mildew from wood.^{[citation needed]} The TSP alone can cause dark stains on redwood, and bleach prevents it.

TSP is used in various forms as a boiler treatment chemical for calcium precipitation, and also to regulate the caustic effects of disodium phosphate in coordinated phosphate chemistry.^{[citation needed]}