Just happened to see this. Look at the last few posts of the "dropping gravel" thread. I was just told that there isn't a GSH that a SMB or HSB can't handle. Excellent news in my opinion. FYI, my HSB were stocked in Oct of 2015. I haven't been able to catch one yet. My YP have had a successful spawn. I'm catching some very small ones. Lots of 9-10" YP though. I'm thinking that's about as big as the males get. I could be wrong.

12 yr old pond, 1 ac, 15' deep.
RES, YP, GS, FHM (no longer), HBG (decreasing), SMB, and HSB (only two have been seen in 5 yrs)
I think that's about all I should put in my little pond.
Otter attack in 2023.