Ok so big changes this weekend. I went through the tank and took everything out and put it into holding tanks to do a little extra cleaning and cleaned out my sump and cleaned off the liverock in my refugium (i.e. put everything through fresh saltwater to get rid of accumulated detritus).
I'd been worried that my levels maybe weren't testing correctly at home, so I took in a sample and found:
Ammonia: 0
Nitrite: 0
Nitrates: Very low (negligible)
Calcium: 405
pH: 8.2
So I'm going to bump up my calcium and buffer my pH a bit. But it gave me enough confidence that I am doing things right and my tank is healthy, I've just had bad luck lately.
So I bought a pair of true percs
They are awesome awesome awesome!
I'll take pictures tonight! They even paid attention to my BTA right away! Not hosting yet, but they brushed against it a few times.
They already ate too, which is a great sign for being newly introduced.