Bought about 30 lbs of LR on April 4 to go into our now empty 67g. The rock was covered in algae, so before putting it into my 20g curing tank, I scrubbed it in changewater from the latest water changes in other tanks with a hard-bristle brush and a toothbrush for the crevices. Water in the scrub bucket got dirty fast, and after scrubbing three rocks, I'd dump the dirty stuff, rinse the bucket in tapwater, then fill the pail again.
This process seemed to take forever, but once cleaned and in the 20g, I could see how nice the coralline was
Every four or five days, I removed each rock and swish it in a pail of SW. Water again got very dirty so I kept changing the water. Also siphoned the crud from the bottom of the tank once during this process and water was also freaking dirty
Ammonia never rose over .5 ppm during curing, so I assume the rock was already partly cured by the time I got it.
Over the past few days, the smell from the curing tank became easier on the nose. Tested for ammonia and nitrite today and both are at 0 ppm
LR after curing:
Close up of cured LR:
67g being filled up with RO.
One more swish of the LR in changewater and into the 67g it will go

After the cured LR is in the 67g, I can get a better understanding about how much more and the shapes/sizes of the LR I'm going to need.