Feeding puppy

Hello everyone!
My new staffy arrived on this Sunday and it is the best dog breed ever. He is happy,he plays all time,but I have some "problems" regarding nutrition. When he was with breeder he ate dry food (Brit care I think),but I have Royal Canin Medium Junior. On label it says puppy eats 200g daily of it,but my dog cant eat that amount,he eats only like 120 or something. Should I worry? Also,breeder told me to feed him with dry food,but I had problems with it couse he dont want to  eat much of it and I started adding water to the food. Is that ok?
Puppy is 2 months old.
Sorry for my English,its not my native language

Hello   Congratulations on your new puppy   I wouldn't worry too much as the guides are just that, a guide, you may find his appetite increases when he has settled in properly. As long as he is fine in himself and not loosing weight. Its fine to add a little water if that helps.

We would love to see some pics of him, this should help with posting them   

https://staffy-bull-terrier.niceboard.com/t12017-how-to-post-a-photos-onto-the-forum

Welcome & congrats on your new puppy! I agree with the above, if he's happy & weight stable then all is ok. I feed my 4 mth old dry and mix a little olive oil or tuna with it to soften it, he loves it.

Aw congrats on your new pup :)He looks adorable!
Just keep an eye on his weight, make sure he doesn't start to get skinny
You are lucky that he knows when to stop and doesn't gorge himself. Bane was underfed when we first got him and we tried giving him the recommended weight on the bag...he scoffed it so fast and was so much more than he was used to he bloated really badly.

Oh and make sure he is having that 200g split into atleast 3 meals a day