not like a balancer at all....
a balancer... is a "balance" of all vits and mins, trace elements ect... yes they include yeast, but not pro or pre biotics.
brewers yeast is a very good product to use, just remember to give a vits and mins supplement alongside it. also with the amounts you would have to feed a horse/pony, plus the vits and mins, it would probably work out cheaper to go for something like "pink powder". a 1kg tub costs about £25 and will last a good few months. contains everything. or bailey's lo-cal is quite cheap too. x
Balancers are a mix of manmade chemicals which many horses do not seem to find easy to actually get into their systems. I feed 50g a day of brewer's yeast, which together with magnesium oxide (magnesium is not easily available in food) and a mixed grass haylage (not pure ryegrass as most are) give all the vitamins and minerals that they needs in a form which is most bio-available (easy for them to get into their systems). Some people add linseed for the omega 3 and 6 and seaweed, but mine don't seem to need those added.
Brewer's yeast is cheapest to buy in bulk. Charnwood Milling deliver 25kg sacks.