Good ideas like this are why I come here. I wasn’t planning on using any of the water - based on the threads I’ve read it seems like I can use 100% new water (someone please correct me if I misinterpreted this!). So yeah I was planning to fill my 44 gallon brute for the rinse, and I think nailing it with the powerhead while they’re still in the 40B would be perfect.How much water are you planning to save from your current system?
You could use a power head and blast all the holes in your current rock as you remove them from the 40B. Then a swish/rinse in clean water.