For mazuri you need to go on their site and check the dealer locator https://www.mazuri.com/Home.asp?Products=2

For Chlorhexidine this is the place http://www.agri-med.com/site/255063/product/CHLRHN2S16 where you will get the best buy ($9.15 per gallons compare to $15/$20 or more a gallons elsewhere) and shipping is very reasonable ($6.99)