A cool vitamin/mineral supplement (australia)?

I'm looking for a vitamin/mineral supplement for my young thoroughbred. I'm just wondering if I try something it might get him hot. He's REALLY EXTREMELY feed sensitive. He can't have any oats or grains AT ALL, it make him rear and really naughty.
He gets twice a year in a 20L bucket, a big handful of salt, 1 scoop pollard, 3 scoop pellets, 2 scoops ezi-result (it's an extra steam extruded feed), rest bursting with chaff, and a flake of hay. Twice a week he also gets 1-2 handfuls of cyllium husk (sp?) as he's kept on sand and it helps move sand out of their digestive tract to prevent colic.
He's a 17hh, 5yo TB. At the moment he's not getting any additional feed from me until he behaves (it makes him muck up a bit which is uncommon cause it's plain and cool) so he's skinnier than he normally is. He's not really skinny, he's just not as butter as he normally is, he's on the lower end of normal solidity.
He's been picking through his/other horses poo too, which is an indicator that he's not getting enough vitamins/minerals.
I just don't want something that could cause him hot. Anyone got any suggestions of supplements preferably available in Australia.
Thanks!
Let me know if you entail more info!
I can single recommend what I used in the past. COOL HORSE AND PONY PELLETS they are only 13 % protein. Rice bran is another that I found to aid put on weight and not heat them up. Salt and mineral block are also good to use.
I hold a couple of questions..
a) why so much salt?
b) what pellets are yiou using and own you tried otherss.
I ask this as we have had troubles in times past we putting weight on hoprses and some feeds being moderately effective rocket fuel.

We had a lot of nouns out of a product called weight lifter(out of victoria I think) but we have another finicky horse who does powerfully on home made mix with wheat bix and Copra in it !!
Answers:    Hi,
I give my boy Equilibrium B1 Cool mineral Mix, I used normal Equilibrium on all my horses contained by the past but as he was is an off the track TB I go with the B1 cool, same as regular equilibrium but had extra dose of B1, apposite for the nervous system :)

I have had nought problems with this and my boy is on a 0 grain diet, for the same root as yours.

I feed him hygain ice, lucern & oaten chaff &speedi beet. morn & night, next to his equilibrium in his night feed and lucern hay at night/whenever he isn't out surrounded by the paddock.

This seems to be working for him at the moment, so I am sticking with it :) he has put on substance and his coat is def better and he isn't too much of a nutter :)

Oh and he is 16.2, TB, 4 years old if that helps :)
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