Pure Dried Vacuum Salt (PDV Salt). This is a high quality food grade salt manufactured in the UK. This salt is ideal for use with koi and other fish and it is the only salt I will use in my ponds There are many advantages to using salt with your fish – •· If your fish are having bacterial issues then salt is a good way of controlling that •· If you are having Nitrite issues then salt can be used to make it slightly less toxic (although salt is not a substitute to water changes) •· Salt can be used to help fish suffering from dropsy and if caught early enough can stop the koi having full kidney failure saving its life. •· Salt can be used against the following koi parasites – White spot. Costia, Chilodonella, Trichodina, Skin Fluke, Gill Fluke, Anchor Worm, Fish Leech. However it is not the preferred treatment of any of these parasites and I personally would only recommend its use as a parasite treatment if you only find say one Trichodina etc on a koi and you are worried that this might break out into something big but don’t want to treat with harsh chemicals such as PP to kill just one parasite. There are some disadvantage that should be noted – •· Constant use of salt in you koi pond will result in the parasites, bacteria etc developing a tolerance to it making it useless. Basically salt best kills unwanted things by shocking them and suddenly dehydrating them but prolonged salt levels will not have this effect. •· Salt can kill koi so if your pond is smaller than you think it is and you over salt you will cause yourself a lot of issues this can be easily solved by buying a salt tester they are easily available on eBay and worth every penny if you wish to use salt regularly. Basically if your koi start floating or going over to one side then there is well too much salt and you should remove the koi from the salt immediately. •· If you are using salt to treat a parasite then keep in mind that the use of salt with some treatments is not recommended so if you have salt in your pond and find yourself wanting to use a chemical make sure you carefully read the manufacturers recommendations carefully.