thats good to know! what if i keep the sand and keep some of the rock that would be okay right?
I would leave the sand in the tank and disturb it as little as possible. Remember any rock you keep you may also be keeping the algae/spores. You could try scrubbing the rock free of any visible algae. Using a couple buckets of saltwater for rinsing.
Your sand and rock are full of nitrifying bacteria/beneficial bactera. The good stuff! Keeping any of it is a good thing.