Use outside only, (there will be fumes) have a hose handy, safety glasses a must with a face shield even better, dont use a metal bucket, wear rubber gloves, and always pour the ACID INTO the water. Neturalize with baking soda if some spills. I'd use a 5 g bucket with about 4" water and add roughly about 2 cup acid to start with. Give it a few minutes. Acid concerntrations will vary with product so read the directions espically on how to dispose when done. Wash hands arms when done. Its not likely going to burn your skin immediatly like you see on TV but as I have found by not wearing gloves little drops you may not even feel get on your skin and start burning 15 minutes later. All this being said, I am new here and a beginner reefer, be safe.
MM