What was the problem of steam driven torpedoes in World War 2 submarine warfare?

Steam powered submarine torpedoes had a flaw when a submarine fired torpedoes in daylight. The torpedoes created a massive stream of bubbles that rose to the surface of the ocean and enemy ships could see that they were under attack. The bubble stream also gave away a submarine's position. This problem was solved for the Germans when they developed electric torpedoes. No bubbles were produced. The US Navy captured some of the enemy torpedoes and used them for models of their own new electric torpedoes.