What color should the stock be? I didn't use tomatoes but expected pink from the shells. Mine came out grayish brown.
I think I rinsed out the tomalley when washing the crud from boiling bubbles off the shells. I used shells from boiled lobsters after removing the heads and swimeretts. The stock had one clove garlic, some celery, onion and carrott.
I also tossed in about a cup of the "sauce" I used for the mussles the same night, I had cooked them in a bit of butter and red wine with a bit of herbs and one diced tomato. I don't think that infuluenced the overall color much because when I first added it at the beginning of the process the water was still very clear and it took a while to turn a bit more colored. I cooked the shells, etc. in water at a simmer for about half an hour and then strained. If I decide to keep it, I will reduce it some more.