So our newest dog is turning into a right handful on walks. He is so calm indoors at home so it's come as a bit of a shock really. When we got him we were told he wasn't so good with other dogs, and as a result we were prepared to avoid them while walking. He also pulls quite a bit, so we've currently got him on a halti which helps. However, since our first sight of another dog it's clear he has some serious issues with dogs. He hasn't been socialised and he's 3 and a half. When he sees another dog he starts pulling and scratching his face to get the halti off which wouldnt be an issue except when he realises this is futile he starts jumping and rearing up trying to get to the dog, no matter how far away they are. Once he's spotted a dog it is impossible to get his attention back and it's really ruining walks for us as i'm on edge constantly incase another dog comes around the corner. Any idea what we can do here? I'd take him to a dog class but I am pretty sure he'd be aggressive to the other dogs. He is however fine with my 9 month old pup within the house, though he will snap if she gets in his way while he's fixated with another dog while out walking. Thanks.