Clean your water holding and mixing containers regularly. Vessels that hold RO/DI water usually don’t get much of a buildup, but saltwater mixing buckets will develop calcium deposits, algae, and other nasty things that can ruin future batches of saltwater. Sometimes a quick rinse with freshwater will clean the bucket thoroughly enough. However, if the buildup is allowed to sit a while, it might take a little extra effort. Vinegar and a little elbow grease will go a long way.