Thankyou all for the avice and replies. i went to see our MCHN today and she said not to stress over the formula. He's just not a milk drinker! Make up a bottle, keep in fridge and add what i can to foods during the day.
His weight is excellent. He's a bit of a booffa. CHN is not concerned he is not getting what he needs.
She is mainly concerned about his calcium intake but said i can up the dairy. She also said i an introduce cow's milk at 10mths, if i choose (i did this with DD).
I have bought the Pentavite multi vitamin to give him. CHN said this would also be of benefit ....maily to easy my mind.