Yes, 30g of chocolate can be harmful to dogs. Chocolate contains theobromine and caffeine, which are toxic to dogs. Even small amounts can cause various symptoms like vomiting, diarrhea, increased thirst, restlessness, and an abnormal heart rhythm. Dark chocolate is more dangerous than milk chocolate due to its higher theobromine content. I once saw a dog experiencing chocolate toxicity, and it was distressing. It’s vital to contact a vet immediately if your dog has consumed chocolate. As a responsible pet owner, I always ensure that my pets don’t have access to chocolate or any products containing it to keep them safe and healthy.