Where do you get potassium nitrate?

Hi I am from germany,does anybody know if it's forbidden for kids(13)?

Get stump remover, then dissolve it in water. Pour the solution through a filter, through a funnel, then into a steel/pyrex container you don't want anymore. Boil the water off and wait for the crystals to start forming. Stop heating it after the crystals begin to form. Drive off the remaining moisture by placing the container with the crystals and a little bit of solution in a warm, dry place until the water is completely gone. What you are left with should be 98%+ KNO₃.

STUMP REMOVER "SPECTRA" BRAND IT IS PURE KNO3
I USE IT IN SMOKE BOMBS AND OTHER AMATEUR PYRO STUFF
YOU CAN GET IT A LOWES HOME IMPROVMENT STORE APPOX $ 4.00 PER BOTTLE 16 -24 OZ

your best off buying off ebay, or, since your in america, pyrounivers, and other fireworks websites, save up, buy a visa debit card from the post office, one with enough money to buy the nitrate, then connect to a paypal account, done, you can buy from those websites.

a word of warning, i have bought stump remover potassium nitrate, and used it, and everything barely worked as expected, i thought it was because of my own mistakes, however, i bought some pyrograde potassium nitrate, off ebay, and the stuff works a treat, everything works, i can even make fuses just with cotton string and dextrin!

the grade in stump remover is generally high in contaminants and stabilizers, or stabilized potassium nitrate, that wont readily decompose the way it should.

its useless for rockets, gun powder, smoke bombs (if you dont want to make one that is more than 800g), and all slow burning or incendary mixtures, though it does burn rather weill with aluminium powder and zinc powder.

basically useless unless your burning it at a tempurature than would normally vapourize it like steam.

my advice is to not use nitrate for rocket engines, and go use some potassium perchlorate instead, which is used in the main ingredient in commercial rocket engines (well all that ive ever been able to buy anyway, i cant vouch for other brands)

its easy enough to make, but be sure to not use chlorate, as that is far too unstable and will explode if mixed with sulfur, or burnt with sugar, if not done properly

You can get potassium nitrate also known as salt peter at pharmisys,as strawberry frtilizer,and as spectricide stump remover other brands don't work.

Potassium Nitrate is the main component of Stump Remover. You can pick it up at Lowe's or Home Depot. Grant's Stump Remover is one of the best stump remover for potassium nitrate. I've used other brands for Sugar/ Potassium Nitrate smoke bombs.

When I was a kid we used to buy small bottles (aspirin sized) of powdered potassium nitrate at the pharmacy. Granted this was the early 90's way before the Patriot act so who knows. We were mixing it with sugar to make smoke bombs. They smell like burnt marshmallows.

It depends on exactly where you live, and what the local agricultural environment is like.
1) It's available someplaces as fertilizer, usually in 50lb bags. "K-power" or similar brands; straight KNO₃ with not much else. Hydroponics grade is the easiest to use. If course, admitting to doing hydroponics might get the drug enforcement folks on you faster than the BATF would ever show up if they thought you were making rocket engines.
2) Several brands of "Stump remover" are pretty pure KNO₃ prills. Sold in 1lb boxes or jars.
3) Ceramics dealers seem to repackage the fertilizer grade stuff as a glaze ingredient. If you have a ceramics dealer that sells glaze ingredients...
4) Some drug stores and feed stores may still be selling KNO₃ as an animal diruretic.
5) Asian markets may be selling KNO₃ as a component for "pickling salt"

unitednuclear.com has all sorts of chemicals. but you should try a flower store and ask for stump remover and check the label to make sure its pure KNO3