RIMS system learn from my (our) mistakes thread

There have been a lot of threads with advice about building a RIMS system but not so much about how to use/troubleshoot. I thought it would be worthwhile to have a thread dedicated to the clusters experienced RIMS users have already worked out. I'll go first...

Problem: stuck mash
The first time I used my system with grain, I ran it with the pump wide open at ~ 6GPM. Within 10 minutes, the pump was screeching as I had compacted the grain bed into an impenetrable slab on concrete.

Solution:
I rinse and soak ~ 2 quarts of rice hulls for about 10 minutes. With the pump turned off, I add the hulls to the grains and stir for a few minutes. I let the grain bed settle for ~ 5 minutes and then turn the pump on low. I gradually increase the flow rate to ~ 2 GPM and have not had any additional issues with stuck mashes, even when brewing with a sizeable amount of rye. I determined the flow rate at 2 GPM through trial and error, but also by watching the fluid level in my sight-glass. The level starts to go down as your mass is sticking but will rise as you lower the flow rate.

Whose next?

Well not using RIMS, but am using HERMS. So I guess it can still be useful.

Problem: Cooling time
Trying to use the HERMS coil to cool the wort for the first time. It took nearly an hour to chill the wort to about 85*.

Solution:
I use a plate chiller with a hop spider and chill my wort from boiling to 75* in about 15 minutes.