As title really, i have tried a few before which haven't worked, so thought it would be best to ask for people opinions on which ones are good and do work.
Hi,
The calmers work by supplementing the horse with magnesium. The horse will only become calmer when being fed one if it has a magnesium deficiency. I supplement my horses magnesium due to her having muscle problems (the magnesium is also important in helping muscles decontract and relax), the cheapest way I have found of supplementing this is feeding magnesium oxide, the countrywide near here sells it quite cheeply as magnitude (equine america) but it is even cheaper online - try these people http://www.naturalhorsesupplies.co.uk/p/category/0802204936-Magnesium+Supplements/ they are also really helpful for dosing info etc. The branded magnesium calmers are terribly expensive and often contain quite a small amount - this should be more effective for a magnesium deficient horse and more cost effective for your wallet!