Gravel and CC are very "oldschool" SW
fishkeeping methods usually used in conjunction with an undergravel filter so you don't have the detrius buildup that you would expect.
I was at a retiree's house last week, who's been keeping SW
fish since he was 14, and for the life of me I could not get him to understand that most SW
aquarists nowadays don't use undergravel filters.
He was using a mixture of large CC and shells.
He also doesn't use any LR
, or do any water changes (and proud of it).
"Young man, I've been doing it this way for 50 years without a problem so I don't see why I would change now"
I was on the clock so I really didn't have time to explain the merits of current methods and practices, but I did give him a link to this forum as well as a couple others so he could catch up on a few decades of reading.
Things have come a long way for SW
aquaria in the last 30+ years since I first went diving with a slurpgun as a kid.
You hardly ever see a SW
tank running a canister filter anymore either, but they're still for sale and some aquarists still use them.
Bottom line is just because we believe we are doing it the "right" way doesn't mean that someone else isn't going to have success using another method.