1. Clean off any sponges, tunicates, etc. that look black and smell rotted.
2. Optional but recommended — dip in a bucket of water and swish/shake to help remove any loose debris / dead critters in the nooks and crannies. (I typically just use tap water since I'm on a well (e.g. non-chlorinated) ... but you can use RODI or salt. I go wish fresh and/or low salinity to help encourage unwanted critters to abandon ship.)
3. Straight into your DT. (The 3 batches I received from Gulf Live Rock did not cause an ammonia spike, but I'm in NC so transit time was fairly short.)