Trouble with TSP – tri-sodium-phosphate

TSP, tri-sodium-phosphate (Na3PO4) was a common cleaner up until about the 1970’s when the massive environmental problems associated with phosphates were addressed by the removal of these chemicals from most products.  TSP is still available in home improvement and hardware stores, as well as on-line, but just because you can buy something doesn’t mean you should use it, at least not without understanding what it is and what the problems associated with it are.

The Trouble with TSP

One thing you may not realize about TSP, which is widely rumored to be very safe and even benign, is that it is in fact highly alkaline, with a 1% solution having a pH of 12 (lye comes in at 11) the highest number on the pH scale, with higher numbers being more alkali.  This means it can and will burn unprotected skin and eyes.  You must read those caution labels carefully.

If you intend to use this product anywhere around plants be sure that you first soak them well with fresh water and then as soon as possible rinse them thoroughly.  That may help protect them.  Products like MoldStat Plus don’t have these same problems and precautions when used around plants.  In fact, they are often used in greenhouses for mold prevention!

The problem is the phosphate

The reason phosphates were banned in the first place is because they cause algal blooms that suck all the oxygen out of bodies of water, killing all life in them.  Creating Dead Zones Because of this, you must be certain that any runoff cannot possibly enter any streams, rivers, ponds, lakes or other bodies of water.  If you have a pond or body of water on your property, you can’t be too careful with TSP.  If it gets into your water feature, you may well have just ruined it for fish, and it won’t be pretty when full of foul, slimy green algae!  MoldStat Plus, and products like it, won’t harm bodies of water.

You can’t just let it run down the sewer drain without care.  In fact, depending on where you live, it may be against local, county, or even state environmental regulations and law for you to even use TSP in the first place.  Using TSP without appropriate precautions could put you in the position of, even unknowingly, breaking the law and facing big fines and penalties if you are caught.  Products like MoldStat are safe and legal to use anywhere in the United States.

TSP Mold removal

If you want to remove mold or mildew you should know that while TSP can remove mildew pretty well, especially if combined with bleach which will remove the color while TSP alone won’t, you should be aware that TSP won’t prevent the regrowth of mold, like products in the MoldStat line can.


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