I think I saw the 41 year old tank pics...if its the one I'm thinking of, it was looking a bit rough.
I think the old tank syndrome is more an issue with deep sand beds that get loaded with detritus (insufficient sand dwelling livestock to keep up with the waste load) or reefs that use crushed coral as substrate. Old tank syndrom manifests itself with contant algae issues and water quality that can't be solved by addressing every other normal problem.
Jim, I know "deep sand bed" usually means six+ inches, so I don't think I need to worry about that with just the two inches I have. And yes, we are still talking about SAND! But, what kind of sand-dwelling creatures would I WANT to have down there? I know I have (at least) a couple of those nasty worms rooting around. I have a brittle star, but I don't believe it ever leaves its reef rock home save to stick out its arms. I never got hermits, cuz I didn't want to deal with the larger homes they'd need, and I think they might eat my snails. So really, I have nothing turning over the fields. Should I be concerned?
Seeing the main idea behind old tank syndrome has to do with the sand bed. How then would I clean mine up, out side of more snails? Without sucking up all the sand?
My substrate doesn't get stirred up much. I do have several tiny nassarius but that's it. I'm concerned about buildup!
many use an adjustable sand siphon. it allows you to adjust the flow so the sand bed gets tumbles but only the finest material is siphoned out, removing detritus but not the sand. personally i have not used one, but basically because i forget to buy one every time im at the LFS.
if you are going this route it is suggested that you only do portions of the sand bed at one time, preventing the possible escape of excess detritus or a cycle.
---------- Post added at 04:53 PM ---------- Previous post was at 04:51 PM ----------
I started keeping pistol shrimp a couple years ago. I have two in my biocube. They rework the sand bed on a daily basis between the two of them. I have two rock pillars in my tank and they each live under one. In my tank that's About 8 inches apart.
The downside is they can bury your corals pretty easily if placed on the bottom