Oh, I have some spider-plant experience! They often die from over-care. I water mine thoroughly and then let it drain and dry out. Then I repeat. Sometimes, 7-8 days might go by without me watering it. And it is thriving and having babies all over the place. Now, my dad got 3 babies from me.. all were dead within a short time. Mine that I kept in the same media (coconut fiber) are thriving now on minimal care. He was overwatering them and their roots rotted.
I don't know if you have wellwater. But some of it is bad, if it is treated with a filter that has salt in it. My mother in law's whole plant collection died before she figured out the reason! Now she uses rainwater with great results.
I used to do indoor growing (tomatoes, hot peppers) and always liked the sevin spray for killing those stupid plant bugs.