Teflon tape, which is wrapped around the threads, or plumber's putty, which is applied to the threads should be quite effecive at stopping the leak. These can be found at any hardward store, and are inexpensive.
don't do it, call a professional plumbing/mechanical contractor to fix it properly.
A roof leak will only be around when it's raining and a plumbing wall leak will be there forever. Which do you have? Food coloring in water and poured down suspected leak paths is very useful. Use different colors.
Repair the pipe of fixture to stop your leak.
The pool liner pad is placed underneath the pool liner to prevent items from cutting through the liner. If the liner is already leaking, the liner pad will not stop the leak.
Replace the line that is leaking, and do not try any stop leak.
because of the leprechauns
A raw egg in to the tank.
A good stop leak product for a radiator is the Bar's line of stop leak. It comes in an easy to pour bottle which seeks out leaks and seals them in minutes.
Most stop leak additives do nothing but empty your wallet. Replace the gasket that is leaking.
you fix the leak
You can use an oil stop-leak product to stop an oil leak on your 2002 Peugeot 206 1.4.
Read the directions on the container of stop leak. There are many stop leak products out there. Keep in mind that this is a temperary fix at best. I suggest that you do not. It causes more harm than good.