when pre-mixing your water for a water change it is best to use a heater and powerhead in the BUCKET of the new water to bring the bucket of water up to the SAME temperature as the water in your tank. Then use a hydrometer to measure the tank water and the new water as you add the salt. be sure to let the salt disolve completely before checking the salinity (the powerhead in the bucket will help with this). once the bucket water and the tank water are the same temperature and salinity you can go ahead and change your water.
Seems like everyone is using Instant Ocean. Does anyone know where to get more information than "contains vitamins and trace elements" for both reef crystals and instant ocean? I want specifics!