Cleaning baby clothes

Our washing machine puts black blotches all over our white clothes but my boyfriend insists it's not from the water softener. With our baby due in November I'm washing all of her clothes today but I don't want her white clothes(which she has a ton of, with colors on them) to be stained. What can I use to ensure her clothes stay white along with the colors staying vibrant? I don't need a spot treatment, I just need a powder, liquid, or tablet to prevent that blotchiness from happening. TIA