Cycling is so confusing. I gave up and just do lots of water changes. I figure the filter will eventually cycle on its own. But that's really too bad you lost so many in 48 hrs. I'm glad you didn't give up because look what you can do now!
My camera has issues with dates. First came grumpy from petco then I found poor lucky in April. Sushi followed shortly after. I had 5 before Grumpy but they all died in less then 48 hours. I'm thinking some type of poisining killed them. I had the filter going but didn't know about the whole cycling of the tank thing.